Polarization, Partisanship, and Health in the United States

Hyperpartisanship and polarization are defining features of contemporary American politics. According to an influential political science measure, Democrats and Republicans in Congress are now further apart ideologically, largely as a result of the GOP's rightward turn, than at any point in the past 150 years (McCarty 2019). Congressional Democrats and Republicans increasingly vote with large majorities of their own party against large majorities from the other party (Lee 2015; McCarty 2019). There are recurrent partisan battles over the federal budget and debt limit, while Democrats and Republicans frequently try to block each other's judicial nominees (Whittington 2018). In the Senate, the filibuster has become much more commonplace as a mechanism for the minority party to stop the majority from passing laws, while rates of legislative gridlock in Congress have risen (Binder 2014). The refusal of President Donald Trump and many Republican lawmakers to accept the results of the 2020 elections, and the efforts by Trump and his allies to stage a coup that would keep him in office, underscore the extent to which American democracy is itself increasingly in peril in a polarized era.

This era of extraordinary polarization and partisanship¹ is hardly confined to Washington. Across the country, similar patterns of growing Democratic and Republican division are visible in state legislatures, although, unlike in Congress, this polarization is also substantially driven by Democrats’ move to the left (Shor and McCarty 2022). Furthermore, there are widening differences between states, which “are much more ideologically divided than they were 25 years ago” (Shor and McCarty 2022: 366). Democratic- and Republican-governed states, often pushed by groups seeking policy changes that are stymied by federal gridlock, are increasingly pursuing divergent policy agendas, with such policy polarization in turn producing divergent socioeconomic outcomes across the states (Grumbach 2022). Accompanying such polarization are rising levels of “partisan federalism” (Bulman-Pozen 2014) where states governed by one party challenge the policies of presidential administrations from the other party (Shor and McCarty 2022).

There is also evidence of accelerating polarization among the public. Liberals and conservatives report intensifying animosity—“affective polarization”—toward the other group, exacerbating political sectarianism, with Democrats and Republicans increasingly viewing the other party as a threat (Abramowitz and McCoy 2019; Finkel et al. 2020). Indeed, partisans now dislike the other party (“negative partisanship”) more than they like their own party (Abramowitz and McCoy 2019; Finkel et al. 2020).

“A growing share of Americans,” Alan Abramowitz (2022: 646) laments, “have come to see politics as a form of warfare, with elections viewed as contests between the forces of good and evil. Partisans increasingly view supporters of the opposing party not as opponents but as enemies . . . Deep partisan divisions, mutual mistrust, and outright hostility toward opposing partisans are [now] the hallmarks of American politics.” Marc Hetherington and Thomas Rudolph (2015: 1) report that “partisans whose party is out of power have almost no trust at all in a government run by the other side,” with a growing partisan polarization of trust in government that makes it daunting to achieve consensus and compromise on policy issues. Meanwhile, the partisan divide in politics is paralleled by “partisan segregation” that separates Democrats and Republicans spatially, as “a large proportion of voters live with virtually no exposure to voters from the other party in their residential environment” (Brown and Enos 2021). And as partisan media proliferates, Americans who consume such sources become less open to opposing views (Baum 2011; Levendusky 2013).

Social identities have played a growing role in sorting Americans into political parties (Mason 2018). “As America becomes more diverse,” Zoltan Hajnal (2023: 39) observes, “it is also becoming more racially divided in the electoral arena.” In presidential elections between 2008 and 2016, about 90% of the Republican nominees’ votes came from white Americans; in 2020, 82% of Donald Trump's voters were white (Hajnal 2023). Religious identity is another major source of division between Democratic and Republican voters as more observant Americans increasingly have flocked to the GOP (Abramowitz 2014). As social and personal identities are more tightly linked to partisan identities the animosity between members of opposing political parties escalates (Mason 2018).

Americans are also increasingly sorted by ideology into political party and increasingly likely to vote straight-party tickets rather than splitting their votes for president and Congress between Democratic and Republican candidates. Studies on polarization among the public have focused mostly on animosity and distrust. But some scholars have documented a growing ideological divide between persons identifying with the Democratic party (who are becoming more liberal) and Republican identifiers (who are becoming more conservative) as they disagree intensely on a host of socioeconomic and policy issues (Abramowitz 2022). Americans’ voting behavior has also transformed. In the 2020 elections, only 16 out of 435 House districts were won by a candidate from a party different than the party of the presidential candidate who carried that district (down from an average of 70 during the preceding three decades) (Bump 2021). In the 2022 elections, only one state—Wisconsin—elected a senator from a party different from the candidate's party that won the state's 2020 presidential contest (DeSilver 2022).

The causes of the growing divides in American politics are uncertain and disputed (Barber and McCarty 2013; McCarty 2019). Gerrymandering—whereby political parties redraw legislative lines to help increase their majorities—is a frequent scapegoat for what ails American politics. But it cannot explain congressional polarization, since the Senate, which is elected via statewide elections and thereby has no gerrymandering, has experienced an increase in ideological distance between Democrats and Republicans parallel to that which has occurred in the House (McCarty 2019). And despite the appearance in recent decades of more partisan media, there is not consistent evidence that such media are making the public more partisan (Prior 2013).

Some political scientists believe rising income inequality has driven polarization (McCarty 2019). Others cite the realignment of partisan affiliations following the Democrats’ embrace of civil rights legislation in the 1960s, Republicans’ embrace of anti-abortion restrictions following the Supreme Court's 1973 ruling in Roe vs. Wade, and the rise of social issues such as gay rights and same sex marriage (Abramowitz 2014; Hajnal 2023; Lee 2015; McCarty 2019,). The sustained period of closely contested elections in the United States since 1980 could also be a cause of partisan (rather than ideological) polarization (Lee 2016). Frances Lee (2014) notes that the current era, characterized by recurrently narrow congressional majorities and tight presidential elections, constitutes “the longest sustained period of competitive balance between the parties since the Civil War.” Because “nearly every recent election has held out the possibility of a shift in party control of one institution or another . . . competition fuels party conflict by raising the political stakes of every policy dispute . . . no party wants to grant political legitimacy to its opposition by voting for the measures it champions” (Lee 2014).

To be sure, the portrait of American politics as polarized can be overdrawn. Measures of ideological distance in Congress may miss fundamental changes in the policy agenda and shifting positions that lead Democrats and Republicans to greater agreement over time on particular issues (Bateman et al. 2016). Such measures of apparent ideological polarization could instead be picking up partisanship that is driven by nonideological factors and does not reflect sharpening policy differences between the parties (Lee 2015). Intraparty divisions in Congress still matter and can severely limit the legislative success of presidents whose parties hold slim majorities in the House and/or Senate. Moreover, partisan fights are hardly a new phenomenon in American political history, and, in recent years, Congress has often enacted laws with bipartisan majorities (Curry and Lee 2020). And much of the public appears, on balance, to be more moderate in its positions than elected officials (McCarty 2019). Despite these caveats, though, there is little doubt that American politics is in the midst of an extraordinary period of partisan polarization.

Polarization and Health Politics

How do partisanship and polarization shape health policy and politics in the United States? Here I sketch out their interactions by focusing on lessons from the Affordable Care Act, COVID-19 pandemic, and other examples.

Partisan Struggles over Enactment

First, political struggles over health care laws may be fought on increasingly partisan lines. While Democrats led the push for Medicare's enactment during the 1950s and 1960s, which was opposed by many Republicans, when Congress finally passed Medicare in 1965 the partisan lines were not as sharply drawn as they would be in later years (Oberlander 2020). Eighty-three Republicans in the House and Senate joined 294 Democrats to vote for Medicare (85 Republicans and 55 Democrats voted against the bill) (Social Security Administration, n.d.).² During the 1980s, there was broad support among Democrats and Republicans for legislation to reform Medicare's hospital and physician payment systems, and, in 1997, the establishment of the Children's Health Insurance Program also drew bipartisan backing (these measures, though, were enacted as part of larger budget bills rather than as standalone bills). In contrast, not a single Republican in the House or Senate voted for the 2010 Affordable Care Act (ACA); in 2017, not a single Democrat in Congress voted for Republican legislation to repeal and replace the ACA. Nor did any Republicans vote for laws enacted during the Biden administration—the 2021 American Rescue Plan Act (ARPA) and the 2022 Inflation Reduction Act (IRA)—that contained reforms to improve the ACA by making its coverage more affordable and, in the case of the IRA, enhance Medicare prescription drug coverage while empowering the federal government to negotiate drug prices for Medicare enrollees.

The passage of the ACA, ARPA, and IRA demonstrate that it is possible to enact major health care legislation in a polarized era if one party controls both the White House and Congress. Indeed, as each party in Congress becomes more ideologically cohesive (including a diminished role for Southern conservatives in the Democratic party and Northeastern liberals in the GOP), it may increase their capacity to pass contentious laws on party-line votes, making use, in the Senate, of budget reconciliation to bypass the super-majority requirements normally imposed by a filibuster. Still, the razor-thin margins of enactment as well as the failure of Republicans’ 2017 ACA repeal bill, the American Health Care Act—which passed the House but lost in the Senate after several Republicans defected—underscore the reality that narrow partisan majorities offer a precarious path to legislative victory. Especially at times when control of Congress and the presidency is divided between Democrats and Republicans, the absence of bipartisan coalitions can inhibit the passage of health care policies.

Postenactment Politics

Second, partisan conflict can reshape a law's implementation and postenactment political trajectory. In a polarized environment, parties may choose to continue fighting against and attempt to undermine a new law rather than accept it (Patashnik 2023; Patashnik and Oberlander 2018). Laws that are passed without bipartisan support may be more likely to face such backlash, especially when an ideologically cohesive party committed to repeal gains majorities in Congress after a prolonged period of being out of power (Ragusa and Birkhead 2020).

After the ACA's 2010 enactment, Republicans mobilized against it in Congress, the courts, and many states (Oberlander 2018). The ACA barely survived legal challenges to its constitutionality that went all the way to the Supreme Court; while such challenges failed to overturn the ACA, they did result in a Court ruling that effectively made Medicaid expansion optional for states. Many Republican-governed states resisted the ACA by refusing to expand Medicaid eligibility or create health insurance exchanges (Béland, Rocco, and Waddan 2016; Jones 2017). And when the Trump administration came to office in 2017, it supported congressional Republicans’ efforts to ACA repeal legislation (Hacker and Pierson 2018). When that strategy failed, it tried to undermine Obamacare through a variety of executive orders and regulatory actions that aimed to destabilize the law's newly created insurance exchanges. Those policies, which did not succeed in achieving their aim, were subsequently reversed by the Biden administration. In a partisan era, a president's executive orders may last only as long as it takes for their successor to overturn them.

Partisan divisions also emerged (and endured) in public opinion regarding the ACA (Chattopadhyay 2018; Hopkins 2023). During the law's first decade, it struggled to attract widespread public support despite the substantial benefits it delivered to tens of millions of Americans and the popularity of some of its core provisions, such as ending insurance discrimination. A major reason for the ACA's underperformance in building a public constituency was its limited support among Republicans. In 2019, there was an astounding 64 percentage point gap in favorable views of the ACA between Democrats and Republicans, and during 2010–19, at no time did more than 25% of Republicans have favorable views of the law (Brodie et al. 2020). Republicans were almost 5 times as likely as Democrats to report that Obamacare had hurt them or their families (Brodie et al. 2020)—a discrepancy that represented an impossible policy outcome but nonetheless illustrated the partisan lenses through which Americans viewed the law. Such divisions reflect “motivated reasoning” whereby the public, following polarized elite rhetoric about Obamacare, interprets media information about the ACA in divergent ways according to their partisan identities (Gollust, Fowler, and Niederdeppe 2020; Jacobs and Mettler 2020). Furthermore, there is evidence that the partisan affiliation of state leaders impacts how some persons view the ACA's Medicaid expansion: “Republicans seem to respond negatively when a Democratic governor announces support for Medicaid expansion, and positively when a Republican governor does so” (Pacheco, Haselswerdt, and Michener 2020).

Partisanship also shaped individual participation in the ACA. Republicans were less likely than Democrats or Independents to join the ACA's insurance exchanges, resulting in lower enrollment that was disproportionately among healthier Republicans, higher premiums for enrollees, and thus worse performance of the new marketplaces in more Republican areas of the country (Trachtman 2019; Bursztyn et al. 2022). However, Republicans enrolled in Medicaid expansions at similar rates to Democrats (Sances and Clinton 2019).

As the ACA's postenactment experiences demonstrate, a polarized environment can disrupt the normal political processes by which a new program builds support among both the public and policy makers. Political scientists expect that new programs will generate positive feedback effects by conferring new benefits and creating constituencies with vested interests in protecting and expanding those benefits, engendering new political dynamics (Hacker and Pierson 2019). But partisan divisions can attenuate those effects by making it harder to mobilize new constituencies and by weakening a program's implementation in ways that reduce or obscure its benefits and hinder both its effectiveness and entrenchment (Oberlander and Weaver 2015; Patashnik and Oberlander 2018). Partisan polarization can lead to prolonged fights over new laws that persist long after their enactment. The controversy and partisan debate over Medicare faded soon after its 1965 enactment, with the program then entering an era of rationalizing politics (Brown 1983) where Democrats and Republicans cooperated on incremental measures to restrain Medicare spending growth. The ACA, though, had a much harder time exiting the realm of existential politics as efforts to repeal it persisted, making it impossible for Congress to produce bipartisan agreement on measures to strengthen the law (Oberlander 2020).³ In short, polarization can create turbulent postenactment trajectories that defy normal political rules and make it more challenging for laws to generate the feedback effects that build their popularity and promote entrenchment (Hacker and Pierson 2019).

Expanding the Scope of Conflict across Institutions

The ACA's postenactment misadventures suggest a third way in which polarization can shape health politics: expanding the scope of conflict to a wider set of institutions. The battles over the ACA were, as noted above, fought not only in Congress and the White House but also in states (Béland, Rocco, and Waddan 2016). Such resistance to the ACA is part of a growing pattern of the minority party in Washington challenging the implementation of laws as well as administrative actions in the states (Dinan 2020). Laws that, like the ACA, create an extensive role for states in implementation are particularly vulnerable to partisan obstruction. A party that loses the legislative battle in Congress can leverage federalism to continue the fight in the states.

The courts, too, have become a venue of partisan conflict. As Jim Morone (2020: 758) observes about the ACA, “After they lost in Congress, the program's opponents successfully moved the debate into the courts.” Republicans—including many state attorneys general—challenged the ACA's constitutionality, often initiating cases in federal courts with conservative judges who were hospitable to overturning the law's major provisions. It is, in fact, hard to make sense of the legal merit of some challenges to the ACA—hard, that is, unless one sees the federal courts as partisan and ideological institutions rather than as impartial arbiters of constitutionality. The legal challenges to the ACA are, as Tim Jost and Katie Keith (2020: 485) write, “politics pursued by other means.” As conservatives have gained an upper hand on the Supreme Court and expanded their influence in federal district and circuit courts, they have increasingly challenged the permissive jurisprudence recognizing an expansive role for the federal government that has prevailed since the New Deal (Morone 2020). Consequently, courts are more willing to overrule health care policies enacted by Congress, thereby rendering programmatic entrenchment more precarious now than at any point since the 1930s (Morone 2020).

In a polarized era, judicial activism can impede the executive branch as well as congressional health policy making. During the COVID-19 pandemic, conservatives brought court challenges to limit federal authority in public health. A group of 21 states—18 governed by Republicans—sued to end the federal mask mandate for public transportation issued by the Centers for Disease Control (CDC) (Diaz 2022). A federal judge in Florida subsequently ruled that the mandate was illegal. And the Supreme Court blocked a Biden administration rule issued by the Occupational Safety and Health Administration (OSHA) requiring larger businesses to either mandate vaccination or masking and testing for their workers (Gostin, Parmet, and Rosenbaum 2022). These rulings, upending what previously had been established as broad federal authority to address public health issues, illustrated the extent to which the courts have become an active front in political struggles over health policy. The Supreme Court's overturning of Roe vs. Wade and the constitutional right to abortion in the 2022 Dobbs decision underscores that “settled” laws and longstanding legal precedents are not beyond reversal in the current partisan environment.

Expanding the Scope of Conflict across Issues

A fourth way in which polarization can shape health politics is by intensifying the partisan scope of conflict in and expanding partisanship to a wider set of issues. The growing distrust between Democrats and Republicans is reflected in their assessments of whether the federal government can effectively respond to disease outbreaks. Between 2006–2014, a period when the avian flu, swine flu, and Ebola emerged as public health issues, Democrats were less confident in the government's ability to respond when a Republican was president, and Republicans were less confident when a Democrat was in the White House (Nyhan 2014).

The extraordinary nature of the COVID-19 pandemic could have been an occasion for Americans to come together around a bipartisan response to a historic public health emergency. But after a brief, initial period of national unity, it morphed into a partisan pandemic (Gollust, Nagler, and Fowler 2020; Gadarian et al. 2022; Mehlhaff et al. 2023). Democratic and Republican-governed states differed in implementation of masking, social distancing, and stay-at-home requirements (Adolph et al. 2021, 2022). The partisan currents running through American federalism made it impossible to generate a coordinated response to a novel virus whose contagiousness did not abide state boundaries.

The pandemic also engulfed public health institutions in partisan controversy, as Anthony Fauci and the CDC became targets for ire over pandemic restrictions. In the pandemic's wake, ideological conservatives are less likely to support CDC's regulatory authority (Motta, Callaghan, and Trujillo 2023). Polling shows that Republicans' trust in an array of agencies involved in public health—CDC, the National Institutes of Health, the Food and Drug Administration, and state health departments—has plummeted (Findling, Blendon, and Benson 2022). Del Ponte, Gerber, and Patashnik (2023) find that “Republicans are less likely than Democrats to believe that the advice of public health experts and medical scientists is in the public interest, and are less convinced that policy makers should follow this advice.” Such partisan disparities are consistent with data showing receding faith among Republicans in scientific expertise in recent decades (Mehlhaff et al. 2023).

By 2021, 26 US states, the vast majority of which were Republican-led, had enacted laws restricting public health authority, including “limit[ing] the power of public health officials to order mask mandates, or quarantines or isolation,” as well as bans or limits on mask mandates and COVID vaccine mandates (Weber and Barry-Jester 2021). In the contentious and increasingly partisan environment surrounding COVID policy making, many local and state public health officials faced harassment (Ward et al. 2022; Barsky 2023).

Polarization can also create partisan conflict in issues that previously had bipartisan politics. During the 1980s and 1990s, there was widespread bipartisan support in Congress for Medicaid expansion that raised income eligibility levels for pregnant women and children (Brown and Sparer 2003). But in the 2010s, as debate over the ACA roared, that bipartisan coalition broke down as Republicans pushed legislation to not only roll back the ACA's Medicaid expansion but also make major cuts in federal funding to states for Medicaid while setting per-enrollee limits on such funding and giving states the option of converting federal funding into a block grant. Those fundamental changes to Medicaid, which would have triggered large enrollment cuts, passed the Republican-majority House and came just one vote shy of enactment in the Senate in 2017 as part of the GOP's ACA repeal-and-replace legislation (Hacker and Pierson 2018). And the Trump administration's enabling of work requirements in Medicaid underscored a widening gap in the parties’ conception of the program as health insurance or welfare.

Medicaid is not the only health care program to be impacted by partisan divisions. The de facto bipartisan consensus that governed Medicare politics during its first three decades was fractured in 1995 when congressional Republicans pursued plans to cap and make substantial cuts in Medicare spending while restructuring the program to accommodate a much larger role for private insurance plans (Oberlander 2003). Since then, Democrats and Republicans have periodically clashed over reforms that would transform Medicare into a defined-contribution or voucher-like program. Meanwhile, the President's Emergency Plan for AIDS Relief (PEPFAR), which has enjoyed bipartisan support since its 2003 establishment, is currently facing opposition to its reauthorization from congressional Republicans as it is ensnared in debates over abortion (Diamond 2023).

Health Behaviors and Outcomes

Fifth, partisanship shapes Americans’ health behaviors and, in some cases, impacts their health outcomes. During the Obama administration, there were substantial differences in Democrats’ and Republicans’ willingness to obtain the swine flu (H1N1) vaccination, driven in part by consumption of different media sources (Baum 2011). A decade later that partisan divide came to define the COVID-19 pandemic. As Republican political leaders, especially Donald Trump but also including GOP governors, began to downplay the threat of the pandemic and the necessity of mitigation measures, Republican voters followed suit and public attitudes and behaviors divided along partisan lines (Mehlhaff et al. 2023; Gadarian 2022; Gollust, Nagler, and Fowler 2020).

Political identity had a major influence on Americans’ responses to the pandemic, with substantial partisan differences in masking, social distancing, and vaccination. The partisan divide in COVID responses has persisted and in some cases widened over time (Clinton et al. 2021). A November 2023 KFF survey (Sparks et al. 2023) reported that 72% of Democrats has already received or intended to receive that fall's new COVID vaccine shot, compared to 23% of Republicans; 9% of Democrats reported never having been vaccinated for COVID, compared to 25% of Independents and 34% of Republicans.

Such behaviors have had profound impacts on Americans’ health. Studies have found higher death rates both in majority Republican counties (after the introduction of COVID vaccines) and among Republican voters (Sehgal et al. 2022; Wallace et al. 2023). Moreover, there are signs that the partisan divisions surrounding COVID-19 vaccination are having spillover effects. While vaccine skepticism decreased during the pandemic among Democrats, it increased among Republicans, who also indicated decreased intention to get the flu shot while Democrats’ intention increased (Trujillo et al. n.d.).

In contrast, before COVID, there was no partisan gap in flu vaccination (Enten 2021; Motta 2023). There is also preliminary data suggesting the politicization of vaccines may be engendering more negative attitudes about childhood vaccines in some Republican-leaning states (Motta 2023). Even policies that seemingly would not divide along partisan lines can polarize the public: Callaghan and colleagues (2023) report that Republicans are less supportive and less likely to use the new national suicide prevention lifeline.

Partisanship can also shape the behaviors of health providers. Bonica and colleagues (2020: 1023) find that “A Democratic physician in a predominantly Republican area is twice as likely to relocate as a Republican counterpart living there; the reverse is also true for Republicans living in Democratic areas. Physicians who do not share the political orientation of their colleagues are more likely to change workplaces within the same geographic area . . . Physicians are actively sorting along political lines.” Areas of the country with higher vote totals for Donald Trump in the 2016 election saw larger increases in the prescription of hydroxychloroquine, a medication touted by conservatives as a treatment for COVID-19 albeit without clear evidence of its effectiveness, after Trump endorsed it (Madanay et al. 2022). However, it is unclear how much of that increase was the result of providers’ preferences as opposed to patient requests for the drugs.

Widening State Differences

Finally, partisanship can widen differences in state health policies. As noted above, states diverged in their approaches to the COVID-19 pandemic along partisan lines. Partisanship has also shaped state implementation of the ACA (Béland, Rocco, and Waddan 2016). While all Democratic-governed and some Republican-governed states have expanded Medicaid eligibility under the ACA, there is a partisan skew in the opposition to expansion. All of the 10 remaining states that have not embraced the ACA's Medicaid expansion have Republican governors and/or legislative majorities. Consequently, low-income adults in those states have an uninsured rate more than twice as high as low-income persons living in states that have expanded Medicaid eligibility (Terlizzi and Cohen 2023). Additionally, the concentration of nonexpansion states in the South “is a source of significant racial inequality in health care access” (Michener 2020: 551) because of their large Black and Latino populations. Moreover, states that have expanded Medicaid under the ACA have seen mortality reductions among populations newly eligible to enroll in the program that nonexpansion states have not experienced (Miller, Johnson, and Wherry 2021).

The ACA's Medicaid expansion also led some states to impose work requirements on Medicaid enrollees as Republican governors who had supported expansion sought to placate conservative voters angered by their embrace of a core Obamacare policy (Fording and Patton 2020). The pursuit of work requirements spread to states that had not expanded Medicaid, further amplifying partisan polarization between the states in their approach to the program.

On a range of issues that impact health—abortion, transgender medical care, environmental policy, gun control, vaccinations, tobacco taxes, paid sick leave, and more—Democratic- and Republican-governed states are moving in strikingly different directions. There is growing polarization in state policy contexts that affect health and also growing divergence in health outcomes between states (Montez and Grumbach 2023). During 1970–2014, states that “implemented more conservative policies were more likely to experience a reduction in life expectancy” (Montez et al. 2020: 669).

Beyond Polarization

In sum, there are myriad ways that polarization and partisanship shape health politics, policy, and health in the United States. However, an exclusive focus on examples of political division can obscure cases where bipartisanship prevails and risks exaggerating both the magnitude and newness of polarization. After all, Democrats and Republicans have long had clashing ideas about health care reform, universal health insurance, and the roles of the government and markets in health policy. The timeline used—the baseline year and comparison point—also matters in evaluating trends in polarization. For example, there is greater bipartisanship today in Congress on the question of whether the federal government should have any role in providing health insurance to the elderly than there was in the 1950s. But there was less partisan agreement on what form Medicare should take in the 1990s than in the 1970s.

Health policy is also multidimensional, covering a staggeringly wide array of issues; Democrats and Republicans are not polarized on all of them. There was, for example, broad bipartisan support in Congress in 2015 for reauthorization of the Children's Health Insurance Program and the reform of Medicare's physician payment update formula. In 2016, wide bipartisan majorities passed the 21st Century Cures Act that aims to accelerate medical product development. There was also strong support among Democrats and Republicans for the 2020 No Surprises Act that seeks to protect consumers from surprise medical bills (Hoadley and Lucia 2022). In 2020, in the midst of COVID's advent, Congress passed the Families First Coronavirus Response Act (FFRCA), which contained numerous health provisions, with overwhelming bipartisan support. And policies such as promoting electronic medical records, value-based purchasing, and accountable care organizations have attracted broad support from both parties (Spivack, Murray, and Lewis 2023). Republicans and Democrats also have sought to preserve the supplemental benefits (and the federal payments that enable them) offered by private Medicare Advantage plans (Kelly 2015). The further away health policy is from Obamacare, the more likely it is to elude partisan acrimony, although, as the congressional debate over prescription drug pricing regulation legislation suggests, such evasion is not guaranteed.

Even the ACA has not consistently been riven by partisan divisions (indeed, the political controversies surrounding Obamacare obscure the fact that it contains policy ideas, such as competition between private insurers, previously backed by Republicans). A growing list of Republican-governed states have joined Democratic-led states in adopting the ACA's Medicaid expansion, including some states where expansion passed via ballot initiative (Rocco, Kelly, and Keller 2020). Forces such as a competitive electoral environment, administrative capacity, prior policy activism, and pressures from the health care industry have propelled some GOP-led states to embrace Medicaid expansion (Jacobs and Callaghan 2013; Rocco, Kelly, and Keller 2020). The politics of the ACA has been more polarized on partisan lines in Congress than in the states, where pragmatism and fiscal interests have often trumped partisan and ideological opposition. And when Republicans tried to repeal the ACA in 2017, the threat increased policy feedback effects among Republicans, boosting the law's public support (Jacobs and Mettler 2020; Mettler et al. 2022).

In state responses to the opioid epidemic, too, there has been some bipartisanship, although substantial differences in funding have emerged between Democratic- and Republican-governed states primarily related to their (non)implementation of Medicaid expansion (Grogan et al. 2020). And North Carolina's recent adoption of the ACA Medicaid expansion with broad bipartisan legislative majorities, following nearly a decade of partisan discord on the issue, is a reminder that partisanship can recede as well as rise.

The ACA and COVID offer compelling examples of how polarization and partisanship can shape health politics. But are these recent examples, which command attention because of both their prominence and recency, the exceptions or a new rule? Is the fight over the ACA a sign of what is to come for other health care programs or will bipartisanship reemerge around issues such as Medicare reform? Has the ACA itself finally moved beyond partisan struggle or could the results of the 2024 election again destabilize its political environment? Will the partisan divide over attitudes toward COVID vaccination continue to spread to other vaccines or recede as we move further away from COVID's dawn?

Conclusion

Polarization and partisanship are crucial dynamics in American health politics. Their impact is wide-ranging, spanning myriad issues in health care policy and public health, different levels and institutions of government, and different stages of the policy process. They shape public opinion about health problems and government policies, persons’ health behaviors and attitudes about public health authority, congressional (in)action, program implementation and administrative actions, federal and state policy making, the courts, and more.

During the past decade, partisan divisions have often defined American health politics. Partisanship undercut the American response to COVID as divisions over the pandemic spread among policy makers, the public, and states, leaving a legacy of divisiveness and distrust that could make it more difficult for the United States to respond to future public health challenges. Meanwhile, partisan polarization on the ACA delayed adoption of policies to strengthen the law and enhance the affordability of health insurance. And it is preventing the United States from adopting reforms that move beyond Obamacare to address persistent issues with insurance coverage, underinsurance, and health care spending.

The opportunities for compromise in health care policy to address the many problems in our nonsystem are made more difficult by partisan and ideological divisions that make adoption of new policies daunting. Hyperpartisanship also injects political instability into the postenactment trajectories of health care programs and policies that are adopted. And if public health is increasingly politicized and its messages are tuned out by a growing number of conservative Republicans, then its effectiveness and reach will be severely undermined. To be successful, public health must resonate and communicate across persons with different political identities and ideologies and in different areas of the country. A public health that speaks mostly to Democrats and persons in urban areas in liberal-leaning states cannot protect the public's health.

This special issue documents some of the many ways in which partisanship and polarization impact health politics, policy, and outcomes in the United States. A crucial question for the future of US health care policy and public health is whether and how these partisan divides can be bridged: Can researchers identify enabling conditions and compelling policies that are conducive to overcoming polarization? There are promising strategies, including ways to reduce partisan vaccine skepticism (Sylvester et al. 2022; Larsen et al. 2023; Algara and Simmons 2023; Motta, Callaghan, and Trujillo 2023), but much more work is needed. A polarized America is ultimately neither a healthy polity or country.

Acknowledgments

My thanks to Eric Patashnik for his helpful comments and timely response to my SOS on an earlier draft of this article.

Notes

References