Finally, Gordon Brown has admitted he made an error. Caught bang to rights by Channel 4 and the estimable Cathy Newman, he grudgingly accepted that evidence he gave to the Chilcot Inquiry was incorrect.
Defence spending has not risen every year in real terms under Labour. He said it had, in public, to Chilcot. The truth was that in three or four years, it actually fell in real terms (and remember, in these years we were involved in two major conflicts). Various Army chiefs criticised his testimony. Gen Sir Richard Dannatt said he was "narrowly and precisely correct", and ex-Chief of Defence Staff Lord Boyce said he was "dissembling" and "disingenuous". Lord Guthrie flatly contradicted Brown's claim that all operational requests had been met, saying that helicopters were requested but were turned down. Brown's response:
"I think they are wrong. To be honest, I don't think it is appropriate for people to criticise us for not providing what we did provide."
Challenged on this in PMQs, Labour MPs shouted that it was all because the Army chiefs were "Tories". The Opposition were, rightly, outraged by this.
And then Channel 4's FactCheck did a bit of FactChecking and, surprise surprise, Gordon was wrong.
Does he take back all those comments about Dannatt and Guthrie and Boyce? Does he apologise to the House for misleading it? Does he offer an explanation of why, when our armed forces are at full stretch in two massive conflicts, with soldiers dying because of poor equipment, he actually reduced the resources available, especially in 2003-4, at the height of the Iraq War?
He does not. Asked by Tony Baldry if he would now set the record straight, his reply was characteristically brusque:
Yes, Mr Speaker, and I am already writing to Lord Sir John Chilcot about this issue ...
Defence spending rose from £21bn to this year around £40bn from 1997 to this day ...
No, it doesn't make sense to me either. But it's typical of Brown to cover any issue he doesn't want to pursue with a barrage of indigestible tractor stats. I'm not saying Brown was lying; I don't think he'd be stupid enough to lie directly to a public inquiry. I suspect he was given the headline points by a researcher and didn't check that they were correct in the way he wanted to use them. But the manner in which this has come out - first, attack your critics, then smear them and their motives, and finally admit you were wrong with as little grace as possible - tells you volumes about the man behind the curious chin twitch.
Graceless, curmudgeonly, tribal - all the faculties you need in a national leader.
The thing is, if he had come to the Commons and said:
OK, everyone, here's an announcement. I made some statements to Chilcot regarding defence, and it has now been pointed out to me that they were wrong. It wasn't deliberate, but I do admit that my research was a bit sloppy, and I apologise to the people I wronged when I denied it, to the House for giving incorrect testimony to a major public inquiry, and to the British people for inadvertently misleading them. Sorry, everyone, and I'll try to make sure it doesn't happen again.
I think that would be worth about 5 percentage points in the polls. But he is constitutionally incapable of that kind of humanity.
I'm going to be giving FactCheck a bit of a closer look in future, too.