Aside from the stunning photograph of Qasem Soleimani’s mangled car outside Baghdad airport, the most astonishing sight after the attack was the universal ambivalence, at best, from Democrats.

Not long ago—before Donald Trump—any president’s use of force against an overseas enemy would get at least 24 hours of partisan restraint. No more. The Democrats’ jack-in-the-box talking point was that Mr. Trump had brought us to “the brink of war.”

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