When the Affordable Care Act (ACA) was passed in 2010, there was a key role for states in its implementation. States were supposed to set up their own health care exchanges, or Marketplaces as they are now called, expand their Medicaid programs, and respond to the many financial incentive-based programs to reform both their local public health systems and health care delivery systems. Despite the rejection of the ACA from conservative-leaning states and the very real possibility that all or significant parts of the ACA will be repealed, implementation questions still loom large for all the states.

By the time this issue goes to press in 2017, states will have had seven years of experience implementing the vast array of ACA policies. This raises many questions: have the states been learning from one another? Do they only take cues from similar ideologically leaning states? Does evidence of effectiveness among first adopters matter for later adopters? Does public opinion affect state adoption and does it influence opinion in non-adopting states? How does framing of policy reforms matter? All these questions and more are addressed in the articles that follow.

These questions are more than mere academic pursuits. And they still matter despite the changing political dynamic that calls into question the stability of ACA-related reforms. The ACA represents the biggest social reform since the passage of Medicare and Medicaid in 1965, and has already dramatically upended how health care is organized in the United States. What states decide to do, or not do, affects whether people have access to insurance (through the Medicaid expansion), what they have access to (through decisions about essential health benefits), and how they receive their care (through delivery model reforms). It is difficult to overstate the importance of prior and future state decisions.

This special issue came about largely due to the insight of the late Andrew Hyman. As Heather Howard's tribute makes clear, Andy was particularly devoted to an RWJF-funded project (directed by Heather Howard), which provided technical assistance to ten states implementing insurance expansions under the ACA. Although Andy cared about improving reforms in those ten states, he would often say, “I want to learn about reform in these states to help improve the implementation of reform across all fifty states.” And then he would ask, “Do we know anything about how to nudge the diffusion of effective policies across the states?” This special issue is an attempt to answer that question. We are thankful for funding from the Robert Wood Johnson Foundation, under the direction of Andy, to hold a workshop focused on the diffusion of ACA policies and to support the development of this special issue.

While seven years is a long time, many of the ACA's major reforms were not fully implemented until 2014, and so it is still difficult to study how ACA policies have diffused across the states. Because of that, we pursued this issue with two objectives in mind: first, we asked scholars with expertise on policy diffusion to write on a topic they know well and with an eye toward what can be learned for ACA policy diffusion; and second, we asked scholars who are knowledgeable about the ACA to study early trends in policy diffusion with an eye toward lessons for future adoption. The result is a combination of articles in this issue: some focused on the ACA, but other articles focused on policies ranging from sales tax for e-commerce to a sample of eighty-seven policies spanning multiple domains and dating back to 1912.

The approach yields some important lessons both for the field of policy diffusion and for thinking back to Andy's question about nudging states along in a meaningful way.

Two articles focus specifically on the ACA, examining the diffusion of state-level decisions about health insurance exchanges and Medicaid expansion. Callaghan and Jacobs use a multivariate analysis to examine what accounts for the variation across states in enrollment. They point out that this question is particularly interesting given the federal government's incentives and mandates, and the “menacing conditions that generally discourage participation” in many states. They find that the early decisions by states are largely explained by party control, but that enrollment is driven by different political and administrative factors for the exchanges and Medicaid. States with higher unemployment had lower levels of enrollment in their exchanges, while enrollment was positively associated with President Obama's vote share. On the other hand, states with higher levels of unemployment had larger enrollment in Medicaid, as did states with higher levels of administrative capacity.

Grogan, Singer, and Jones examine the rhetoric used by seven Republican-led states to secure 1115 waivers in order to pass legislation expanding Medicaid. These waivers have been integral to convincing conservative legislators in these states that the changes to Medicaid are sufficiently different from the traditional program and from the ACA. Grogan, Singer, and Jones use a content analysis of media coverage and press releases to argue that the policies proposed in each subsequent waiver were further to the right of their predecessors though the associated rhetoric remained consistent. Proposals for introducing premiums, cost sharing, and work requirements into Medicaid were discussed as returning the program to its original intent of caring only for the “truly needy.”

Two articles add to the growing political science literature about how policies spread across governmental units, with an eye toward lessons for the ACA. Boehmke et al. take an applied approach by performing simulations to understand which states have the largest impact on speeding up the diffusion process. They select a variety of different “seed” states and find that policies spread much faster and more extensively when policies are adopted first in leader states. This is important for policy advocates who have limited resources, but who want to have the largest impact across the American states. If we want to “nudge” policy along, Boehmke et al. suggest concentrating efforts in states that are policy leaders.

Pacheco and Maltby explore the role that public opinion plays in the diffusion of ACA policies. They find that both gubernatorial ACA announcements and grant activity increased support for the ACA in nearby states. However, only gubernatorial announcements respond to shifts in ACA support, presumably because it is a more salient policy than grant activity. They also look at whether shifts in public opinion in other states provide a signal to elected officials about the viability of decisions in their own state. They find states are more likely to emulate other states with similar ACA policy preferences when deciding about when to announce their decisions. Public opinion may be a potential lever that advocates use to accelerate the diffusion process—either by actively framing the policy debate in ways that are favorable toward their policy or by advising state legislators about public support in similar states.

Karch and Rosenthal look to the debate over applying a sales tax to electronic commerce to draw lessons for the ACA. They argue that this episode, along with the scholarly literature on framing effects, should cause us to question whether supporters of the law will be able to improve public opinion about the ACA by shifting attention to its more popular components. Instead, engagement would be a more effective rhetorical strategy. Advocates should address the same policy dimensions as their opponents and try to convince conservatives that the reform can accomplish what they care about, such as reducing taxes or expanding the role of the private sector in government programs.

We also have two commentaries: one from Craig Volden and a coauthored piece from Rena Conti and David K. Jones. Volden considers how the articles in this special issue contribute toward what we know about the diffusion of policy choices across the American states, and how that knowledge may help us understand the past, present, and future of the ACA. He argues and illustrates how both the ACA and policy diffusion more generally have been significantly affected by the polarized times in which we live. Conti and Jones focus on what policy diffusion research might gain from literatures that focus on the role of private actors. They highlight two important insights for future research: first, after detailing how multiple ACA policies are simultaneously under consideration for adoption in each state, they argue for shifting the focus on the diffusion of specific policies to a diffusion of “policy packages”; second, they discuss why it is important to consider how federal policies impact private actors, especially because a changed private health care marketplace will impact how states approach the adoption and design of specific ACA policies.

Taken together, these articles paint a comprehensive picture of the complex nature of the diffusion of policies stemming from the ACA. We learn that there are some predictable patterns at work, but that policies do not necessarily spread because they are the “best.” Diffusion does not necessarily happen because policy makers are learning, and when there is learning it can be about the political effects as well as the policy outcomes. Thus, to return to Andy's question, there are levers for change that state policy makers and other political actors can pursue, but these levers do not distinguish between “good” and “bad” policies. Obviously, these terms are subjective. We want to create a nudge for diffusion of effective policies, but who decides which policies are most effective? We want states to learn from one another, but not at the expense of a democratic process. Sometimes bad policies diffuse. What then? And, what happens if we want to stop a policy? Perhaps this is the story of the ACA: those who want the reform are busy implementing and learning from similarly reform-minded states, and those who are against reform are busy fighting to stop it and learning from similarly resistant states.

This is the essence of democracy under a federal system, for better and for worse. There is enduring debate about whether or not just policies are most likely to emerge from democratic systems. We know that some of our worst, most inhumane policies have emerged out of democratic systems. Yet, we also know that many of our state political processes fall far short of the democratic ideal and many voices are systematically excluded. So, if we strive for any lever to nudge change in the right direction, perhaps it should be that which brings about the most fair and open democratic process in each state, with no guarantees but hope that just policies will prevail.

Finally, we have one last Behind the Jargon in this issue. I want to thank David Frankford for acting as editor of this special section for six years. He has brought forth numerous gems for helping us think more deeply about the assumptions underlying some of the most popular jargon used in our health policy lexicon. These essays force us to confront what's at stake when jargon, such as “crowd-out” and “moral hazard” (just two examples of many essays), are used unquestioningly. Jargon assumes agreement on defining a health policy problem, and equally important, it often points in one direction for policy solutions at the expense of considering alternative paths. We use jargon unquestioningly, often to our peril, and David has helped us see that.

Freely available online through the Journal of Health Politics, Policy and Law open access option.