The lead-up to the House passage of the American Health Care Act (AHCA) in May, which passed by a narrow majority after a failed first attempt, provided a glimpse into just how difficult it is to gain consensus on health care coverage.

In the aftermath of the House vote, many people have asked: Why are politicians struggling to find consensus on the AHCA instead of pursuing universal coverage? After all, most advanced industrialized countries have universal health care.

Research from political science and health services points to three explanations.

No. 1: American culture is unique

One key reason is the unique political culture in America. As a nation that began on the back of immigrants with an entrepreneurial spirit and without a feudal system to ingrain a rigid social structure, Americans are more likely to be individualistic.

In other words, Americans, and conservatives in particular, have a strong belief in classical liberalism and the idea that the government should play a limited role in society. Given that universal coverage inherently clashes with this belief in individualism and limited government, it is perhaps not surprising that it has never been enacted in America even as it has been enacted elsewhere.

Public opinion certainly supports this idea. Survey research conducted by the International Social Survey Program has found that a lower percentage of Americans believe health care for the sick is a government responsibility than individuals in other advanced countries like Canada, the U.K., Germany or Sweden.

No. 2: Interest groups don’t want it

Even as American political culture helps to explain the health care debate in America, culture is far from the only reason America lacks universal coverage. Another factor that has limited debate about national health insurance is the role of interest groups in influencing the political process. The legislative battle over the content of the ACA, for example, generated US$1.2 billion in lobbying in 2009 alone.

The insurance industry was a key player in this process, spending over $100 million to help shape the ACA and keep private insurers, as opposed to the government, as the key cog in American health care.

While recent reports suggest strong opposition from interest groups to the AHCA, it is worth noting that even when confronted with a bill that many organized interests view as bad policy, universal health care has not been brought up as an alternative.

No. 3: Entitlement programs are hard in general to enact

A third reason America lacks universal health coverage and that House Republicans struggled to pass their plan even in a very conservative House chamber is that America’s political institutions make it difficult for massive entitlement programs to be enacted. As policy experts have pointed out in studies of the U.S. health system, the country doesn’t “have a comprehensive national health insurance system because American political institutions are structurally biased against this kind of comprehensive reform.”

The political system is prone to inertia, and any attempt at comprehensive reform must pass through the obstacle course of congressional committees, budget estimates, conference committees, amendments and a potential veto while opponents of reform publicly bash the bill.

Bottom line: Universal coverage unlikely to happen

Ultimately, the United States remains one of the only advanced industrialized nations without a comprehensive national health insurance system and with little prospect for one developing under President Trump or even subsequent presidents because of the many ways America is exceptional.

Its culture is unusually individualistic, favoring personal over government responsibility; lobbyists are particularly active, spending billions to ensure that private insurers maintain their status in the health system; and our institutions are designed in a manner that limits major social policy changes from happening.

As long as the reasons above remain, there is little reason to expect universal coverage in America anytime soon.