The videos can’t account for every shift in the polls. Advances by ISIS on the battlefield no doubt played a role, as did panicky rhetoric from U.S. politicians. Still, it’s noteworthy how much of the surge in enthusiasm for military action occurred during the period in which the videos were released, as opposed to the period in which Obama declared ISIS a threat to U.S. interests and launched strikes against it. In the June ABC/Post poll, only 45 percent of Americans endorsed “U.S. air strikes against the Sunni insurgents in Iraq.” Fewer than half of these supporters (20 percent of the total sample) said they supported such airstrikes strongly. By Aug. 13–17, a week after Obama’s announcement, support had increased by about 10 points: 54 percent supported air strikes, and 31 percent supported them strongly. But by Sept. 4–7, after the Sotloff video, support had climbed much higher. Seventy-one percent of Americans supported air strikes, and 52 percent supported them strongly. From these numbers, one could argue that the ISIS videos were twice as effective as Obama in rallying American support for war…

U.S. military leaders call ISIS a “learning organization.” But a learning organization would have figured out by now that its videos, despite their message to stay out, were having the opposite effect. To rationalize the continuing production of videos, you’d have to postulate that ISIS, while trying to form an infant caliphate, wants to engulf itself in a war not just with the United States, but with European military powers (and Australia and Canada) as well. That’s just too far-fetched.

There’s a simpler explanation. ISIS isn’t a learning organization. It’s a killing organization. And it can’t stop killing, even when what it’s killing is itself.