What's interesting about this is General Petraeus is actually being somewhat honest about this. Any policy that could have even a miniscule chance for a "Bush-style victory" in Iraq WILL require long term commitment of hundreds of thousands of US troops. Indeed, a do-over is required. Dissolution of the existing pro-Iranian Iraqi government, imposition of shared political power and gradual transition to a democracy. Yes the early imposition of elections was the greatest mistake in the posat-invasion Bush policy:

Rapid democratization, meanwhile, could be positively harmful in Iraq. In a Maoist people's war, empowering the population via the ballot box undermines the insurgents' case that the regime is illegitimate and facilitates nonviolent resolution of the inequalities that fuel the conflict. In a communal civil war, however, rapid democratization can further polarize already antagonistic sectarian groups. In an immature polity with little history of compromise, demonizing traditional enemies is an easy -- and dangerous -- way to mobilize support from frightened voters. And as the political scientists Edward Mansfield and Jack Snyder have shown, although mature democracies rarely go to war with other democracies, emerging democracies are unusually bellicose. Political reform is critical to resolving communal wars, but only if it comes at the right time, after some sort of stable communal compromise has begun to take root.

Of course it is inconceivable that any of that is possible. Thus, failure in Iraq is and has been upon us for years. All that is left is the butt covering.