Indeed, the mass scramble for the "Exit from Responsiblity for War" is not that edifying. On the other hand, it's perhaps an acknowledgement of some things.
For example, my theory about the war is that entry into it was structurally determined by the principles underlying New Labour, themselves determined by the experience of electoral defeat in four elections. The major determinant was, I think, a feeling that Labour had to show itself very willing to accommodate established power; the markets, the "special relationship"; not be seen as too radical, or wanting to rock the boat too much.
So, entry into the war wasn't an accident, a temporary aberration, and it can't be put down to individual egomania (of Blair), which I think some apologists have tried to do.
I see the stepping away from the war as a signal that there is a feeling that that accommodation went a bit too far, and a recognition that it alienated a lot of the core vote.
It would be really interesting to hear what psephologists have to say about who did, or did not, vote for Labour this time. Did they lose core voters?
In my dreams, I see a lot of the bits of New Labour I'm not so fond of as having been determined by the wishes of the over-powerful C2s. And, again I come back to my hope for PR and a diminution of that power.
Warning - all this is just pondering - I have nothing, at all, to justify any of these opinions!!