The cynic and realist in me has always thought, and responded when asked, that if you get the casualty number below 20, or roughly half the number of the war months, then the question of withdrawal would evaporate.

Seeing the page 6 coverage of 18 deaths in May, that logic seems to be holding nicely.

As I said all along: the only measure is U.S. casualties. Progress or no within Iraq, so long as losses are perceived low, the time line stretches plenty. With reasonable progress, like we're getting, then we're into the very positive dynamic of accumulating time since the last great spasms of civil violence.

In that space we fill up, as much as possible, on economic development, with Enterra working the Kurds in the lead, setting the example for elsewhere.

And so long as our casualties stay low and stability spreads, then time is on our side and it becomes apparent to Iran that they have to start picking sides among the Shia in Iraq, no longer backing all in a hedging strategy.

And then the opportunities emerge, once Bush is gone and Ahmadinejad suffers election defeat.

Nothing overnight, but things progressing nicely, and no matter all the legit negatives you can toss at Petraeus, these are the only wins that matter, and so he gets plenty of credit.