Trade war is Trump’s hammer, and everything looks like a nail.

This should be no mystery, because trade war is also the centerpiece of Trump’s domestic policy. Asked at the debates about the solvency of Social Security, he answered that he would impose tariffs on China and bring jobs back to the United States, and this would pay for everything. So if trade war is his plan for entitlements, debt, and economic growth, why shouldn’t it also be his plan for China, Russia, North Korea, and rebuilding the military?

Even if trade war were a good idea—and it isn’t—it does not constitute a coherent foreign policy. But for Trump, it’s a fixation.

Unfortunately, this is also a popular fixation for a large portion of voters who are eager to blame everything on foreigners stealing our jobs. That is to say, it is a foreign policy perfectly calibrated to win Republican primaries in places like Pennsylvania and maybe Indiana, among blue-collar voters who don’t really care about foreign policy. They were the real audience for Wednesday’s speech.