Everything that’s wrong with America is Barack Obama’s fault. That’s what Republican politicians have told themselves and the public for eight years. It began before Obama took office, when Republicans blamed him for a recession that started on their watch. Now they’re blaming Obama for the rise of their own presidential front-runner, Donald Trump.

The delusion that Obama caused Trump has been building since last year. This week, it reached the last bastion of rationality on the right: New York Times columnist Ross Douthat. Douthat has a long track record of fairness and good sense. When the madness infects even him, it’s time to clear the air. No, Obama didn’t cause Trump. What caused Trump was the GOP’s decision to negate Obama in every way, and thereby become the party of Trump.

As president, Obama was never a radical leftist. He extended the drone program, the Iran sanctions, and the bailout-recovery policies of George W. Bush. He proposed to cut the national debt through a higher ratio of spending cuts to tax increases than even Bush’s father had accepted and Republican voters preferred. Obama embraced the Heritage Foundation’s idea of imposing personal responsibility for health care costs through an individual mandate to buy insurance. He decimated al-Qaida’s leadership, built up troop strength in Afghanistan, and killed Osama bin Laden.