The NYT reports on the progress of the "surge":
The American assessment, completed in late May, found that American and Iraqi forces were able to “protect the population” and “maintain physical influence over” only 146 of the 457 Baghdad neighborhoods.
In the remaining 311 neighborhoods, troops have either not begun operations aimed at rooting out insurgents or still face “resistance,” according to the one-page assessment, which was provided to The New York Times and summarized reports from brigade and battalion commanders in Baghdad.
The U.S. is only able to hold a third of Baghdad. But the NYT gives some false hope:
The last remaining American units in the troop increase are just now arriving.
But it neglects to say that the last arriving brigade is the 3rd Infantry Division’s Combat Aviation Brigade with lots of helicopters but no feet on the ground. They may shoot up another primary school, but are not of much use for holding ground.
The number of troops could still be increased, but only by prolonging tours for GIs already in Iraq.
As others have pointed out here, U.S. General Sanchez and U.K. General Rose both assert that victory is impossible, a stalemate the best possible outcome and a defeat the most likely.
To hold more of Baghdad many more troops are needed. Baghdad by now has probably some 5 million inhabitants left, down from 6.5 millions before the war. A decent counterinsurgency rate would be one trooper for each 50 inhabitants. But currently there are only some 30,000 U.S. soldiers in Baghdad, less than half of those actually on the streets, plus an unreliable auxiliary force of some 20,000 Iraqi soldiers and policemen.
"Clear and hold" is not achievable if the "hold"-forces are much smaller than the "clear"-force. Therefore this obviously does not pan out:
The battalion’s troops, augmented by more than 2,000 soldiers in armored Stryker vehicles, went block by block through the neighborhood, arresting suspected insurgents and destroying arms caches.
But since the Stryker unit has moved on to a different area of Baghdad, “there’s been a reinfiltration” by Shiite fighters and intimidation squads, who had left the area when the operation began, said Capt. Tim Wright, the company commander responsible for the neighborhood.
Where to go from here?
Over the next six month the insurgents will more and more unite against the occupation. There are already signs of Shia and Sunni cooperation in Diyala province north of Baghdad. The recent announcement of long term "Korea like" U.S. intentions will accelerate the process.
The small U.S. Forward Operation Bases (FOBs) will come under continues attacks, some will be overrun and with rising casualties the U.S. troops will retreat to the bigger bases. There is little chance that these big bases can be attacked by direct force. But they can be suffocated by cutting through their supply lines.
Already bridges seem to be a prefered target. The airforce will of course "guarantee" that it can supply the bases by air transport. Goering also promissed to do so for the enclosed Germans at Stalingrad.
There are a few wild cards. The U.S. might try to kill al-Sadr, currently the most likely attraction point for a united national insurgency. Turkey, already shelling accross the border, may be pushed by its right wing military into a deeper incursion into Iraq. As the U.S. has recently transfered responsibility in north Iraq to the Kurds, it may just wash its hands in innocence over this, but doing so will certainly not gain favor with the Kurdish fractions.
The biggest wild card is still Cheney’s attempt to start a war with Iran. Any 9/11 like domestic incident or any serious naval accident near Iran may generate sufficient support for such a campaign. If that happens, all bets are off.