Waiting until Sunday night to file a Monday column puts stress on editors, and I try not to do it. But I waited this week until shortly before 5 P.M. Pacific time, as I was genuinely concerned that the jihadists had in fact organized something to wreak havoc on our national celebration.

My friends inside the intelligence community and within the Congress and with access to most of the highly classified material on the “threat stream” were deeply concerned, and in a way they had not been before, not since the days after 9/11.