Josh Kraushaar warns National Journal readers that the 44th president’s signature piece of legislation — ObamaCare — could end up having a negative unintended consequence for his political allies.

In fact, the legacy of the Iraq war to Republicans during the Bush administration offers a useful reference to how the implementation of Obama’s health care law could play out politically for his party. Like the Democrats’ partisan relationship with the health care law, support for the Iraq war was a prerequisite for being a Republican during the Bush years. Opposition from the rare gadfly, like Ron Paul or Walter Jones, nearly drummed them out of the party. Among Democrats, outspoken antipathy to the war was most intense among the base – the netroots and antiwar activists at the fringes of the party. For a while, most Democrats didn’t want to sound too critical of the war effort for risk of being painted as part of the anti-war movement.

Support for the war dropped as officials struggled to implement nation-building after the fall of Saddam Hussein. As casualties piled up and the violence worsened, the fringe position of the liberal base gradually became more palatable. No longer were war-critiquing Democrats seen as soft on national security. In the 2006 midterms, Democrats effectively campaigned on an anti-war message to take back the majority in the House and Senate for the first time in 12 years, capitalizing on war weariness. Eventually a number of Republicans split from the party to save their political hide.

While the debate over Obama’s health care law isn’t a life-or-death battle, health care affects voter livelihood (and their voting decisions) like few other issues do. And there are clear signs that if premiums go up, businesses are forced to change how they insure their employees, and implementation of the law is uneven, the potential for political consequences are significant. In the 2010 midterms, Democrats suffered a historic landslide when the debate over health care was abstract. The stakes could be even higher when voters have first-hand experience with its effects. (Just look at the fevered reaction from Hill staffers affected by the law for a sampling of how intense voter anger could become.)

In both examples, the presidential sales pitch ended up being overhyped, with promises made that couldn’t realistically be achieved. At its heart, the mission to oust Saddam Hussein was about preventing a dangerous tyrant from using weapons of mass destruction – but administration officials advocated everything from democracy promotion to preventing an alliance between Iraq and al-Qaida as part of its overall argument. When events turned south, failure to achieve many of the items on the checklist proved politically embarrassing.

Obama’s health care law was designed to expand access to the uninsured. It’s a noble goal, if not necessarily a smart political priority. (It’s more popular to advocate for improved health care, not expanded access.) But to win support for the law, Obama claimed it would lower costs, improve the quality of care and not force anyone off their current health care plan. That’s not shaping up to be the case.