When I heard David Davis had decided to resign as an MP and Shadow Home Secreatry, two events crossed my mind:
1) The resignation of Michael Heseltine from Margaret Thatcher's Government in January 1986.
2) The sight of David Davis, despite his obvious discomfort, supporting ID cards when Michael Howard led the Conservatives in 2004.
What I find extraordinary is why this man of such high principle (so we are led to believe) did not resign back in 2004. I hope someone asks him this weekend.
On the politics of all this, Conservative HQ spins frantically that there was no disagreement between Davis and Party leader David Cameron but few are convinced. The Cameron line (backed this evening by Davis's replacement, Dominic Grieve) is that they will consider abolishing the 42-day rule once in office.
Nothing very equivocal there - indeed, one might argue Cameron is trying to have his cake and eat it too. On the other hand, he wants to be seen to be close to the "man of the hour" but on the other he wants to keep the authoritarian populists in the media and, if the polls are to be believed, among the majority of the public, on side. This will be a tough tightrope to walk.
Perhaps Davis came to realise Cameron would ditch him after the General Election - perhaps he thought it would happen sooner and decided to "do a Heseltine". Whether there is a real ideological split within the Conservatives between the Cameronites and Davisians I doubt - the reality of the proximity of power precludes this.
However, Davis HAS put down a marker of sorts and he may be the beneficiary if or when a future Cameron Government hits trouble. That may be to read too much into this - only Davis really knows the truth and we may not hear that for some time.