The problem with the legend of the surge is that it reproduces the very hubris that led America into Iraq in the first place. In 2003, the Bush administration believed it could shatter the Iraqi state and then quickly and cheaply construct a new one that was stable, liberal, democratic, and loyal to the United States. By 2006, many conservatives had realized that was a fantasy. They had massively overestimated America’s wisdom and power, and so they began groping for a new approach to the world. But then, in 2007 and 2008, through a series of bold innovations, the United States military bribed, cajoled, and bludgeoned Iraqis into multiple cease-fires. The Iraqi state was still broken; its new ruling elite showed little of the political magnanimity necessary to reconstruct it in an inclusive fashion. And the Band-Aids that Petraeus and his troops had courageously affixed began peeling off almost immediately. Nonetheless, Republicans today say the Iraq War was won, and would have remained won, had the U.S. left 10,000 troops in the country after 2011.

How much damage will the GOP’s revived hubris do? Inconceivable as it would have seemed a few years ago, Graham, who is now a Republican presidential hopeful, has suggested sending 10,000 American ground troops back into Iraq. (His GOP rivals generally support this idea but have not proposed exact troop numbers.) The U.S. is unlikely to send a sizable American ground force back into Iraq. But this line of thinking is troubling nonetheless, because the same wild overestimation of American power that fueled the war in Iraq now fuels the right’s opposition to the nuclear deal with Iran. To hear hawks tell it, the United States can scuttle the current deal, intensify sanctions, threaten war, and—presto—Tehran will capitulate. But Iranians have been living under the threat of attacks from America or Israel for more than a decade now. And British and German diplomats have warned that if the U.S. Congress torpedoes the agreement, sanctions pressure on Iran will go not up but down, as countries that have lost billions by limiting their trade with Tehran stop doing so.