Americans used to think that the federal government should make sure everyone had access to health insurance. As recently as 2006, 69 percent of those surveyed by the Gallup Organization said that “it is the responsibility of the federal government to make sure all Americans have health care coverage.”

By 2013, however, the fraction had eroded to 42 percent, with a clear majority (56 percent) reporting that Washington is not responsible for ensuring health care coverage for all. Why the shift?

The facile answer is that the passage of the Affordable Care Act (ACA), also known as Obamacare, in 2010, exposed Americans to the reality of government involvement, and they didn’t like what they saw. Between 2010 and 2013, the share of Americans who said that the government is responsible for making sure all of us have health care coverage declined from 50 to 42 percent, while the fraction who said that it isn’t the government’s job increased from 50 to 56 percent.

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The implementation of the new law has undermined Americans’ confidence in the government’s role. The flawed rollout of the online health care exchanges, repeated delays of the employer mandate, and flip-flops on whether to allow continuation of low-cost catastrophic coverage, have no doubt changed some minds.

Support for the new law has ebbed in recent years. Gallup reports that the fraction of Americans who approve of the health care law declined from 48 percent in December 2012 to 40 percent in February 2014. Real Clear Politics puts the average perception of the new law across the set of polls examining the question at 54 percent negative and 38 percent positive.

Thus far, Americans think that the new health care law has caused more harm than good. A Rasmussen Reports poll conducted at the end of February showed that only 14 percent of Americans think that the law has helped them, while 33 percent believe that it has hurt. A similarly-timed Gallup poll showed that 23 percent of Americans see the law’s effect on them and their families as negative, while 10 percent view it as positive. Gallup also found that only 21 percent of Americans think that the new law will improve their family’s health care situation in the long run, while 40 percent think the ACA will worsen it.

But, as those running for Congress in 2014 should note, the ACA alone cannot account for the shift in opinion. Much of the change occurred before the passage of the Act. Between 2006 and 2008, the fraction of Americans who said that the government is responsible for ensuring that everyone has health insurance dropped from 69 to 54 percent.

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The Gallup organization suggests that President Obama’s focus on the issue in his first campaign and subsequent efforts by him and Democratic leaders to push for and pass the ACA, politicized the issue.

Perhaps, but the data don’t support that assertion. The negative shift transcends political boundaries. Between 2006 and 2010, the fraction of Democrats who believe that the federal government is not responsible for ensuring that all Americans have health care coverage rose alongside the share of Republicans and Independents.

Perhaps the shift stems from a medium term change in priorities. The fraction of Americans who reported to surveyors from the General Social Survey that the country was “spending too little money on improving and protecting the nation’s health” declined by 14.4 percentage points between 2006 and 2010, while the share that said the country was spending too much money rose by 11.6 percentage points.

Whatever the cause or causes, I can tell you this: those running for House and Senate seats will want to figure out why Americans’ attitudes have shifted. The federal government’s role in health care will be a major issue in the 2014 Congressional elections.

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