Maybe this sense of increased unease is just subjective; I don’t know any rigorous way of measuring it. But I suspect that part of the reason is because this is the first anniversary of September 11 to fall in the era of Donald Trump. No, I don’t mean this as a reflexive dig at his competence as a leader. There is a much deeper meaning to it, which has two parts.

The first is what David Harsanyi has pointed out: after an astonishingly brief period of national unity and bipartisanship after September 11, we’re at each other’s throats more than ever. The political debate got vicious, bitter, and personal in the later Bush years, it got worse under Obama, and Trump’s election—from the chest-thumping arrogance of his supporters to the hysterical “resistance” fantasies of his detractors—has somehow managed to make it much, much worse.

More deeply, however, I suspect people are beginning to sense that this is the first 9/11 anniversary where neither political party really cares all that much about its meaning and legacy—not enough to do any serious thinking about the long-term answer to the threat of Islamic terrorism.