Well, Operation Spear is underway in Karabilah; as usual it’s a forgone conclusion that the insurgents will lose. The only question is how many will be captured, how many will die, and how many will run away. I’m curious whether this is one of the two new large operations Jaafari alluded to, or whether those are all-Iraqi missions. Either way, it seems more pressure is coming to bear on the insurgency as Iraqi forces continue to grow and improve.
Michael Totten notes Niall Ferguson made the argument yesterday that we need 1 million troops based on the 1920s British experience, but I tend to view it as suspect for several reasons, not the least being that force multipliers like LRAS, body armor, night vision, precision munitions, and close air support make 100,000 modern U.S. troops able to do more than a million WW II soldiers could dream of, let alone WW I era soldiers. Another major difference is that we're not trying conquer Iraq, just defend the elected gov't, and for that reason most of the citizenry is on our side. Also, the size force Niall contemplates would require such massive logistical support that it would further burden the strained local infrastructure, generate massive local resentment, create a lot more targets for suicide bombers, and it's hard to see what more they could really do than is being done now. It's not like we're being overrun by vast numbers of insurgents; our main problem with defeating the insurgency isn't manpower, it's finding the insurgents, because they won't come out and fight (they've learned they always lose a straight fight regardless of numbers). A nonsectarian native Iraqi force, loyal to democratically elected leaders, that can better gather intel is probably the best solution available in an imperfect situation.
A commenter named RickW just back from Iraq also chimed in with the question of what a million troops could do that isn't being done now. Another military commenter also made of the same arguments I did above, noting in more detail the specific logistical problems 1 million troops imposes.
The number of troops seems about right for the tasks they're doing, which increasingly are training-related. Austin Bay reports Iraqis are now providing half the forces in 90% of operations, and are begining to take responsibility for entire AOs.
I think there is a terrible lack of perpective among the chattering class on what it takes to win a counterinsurgency, esp. how much time, probably partly driven by how easy the war to remove the regime was by comparison. By this time next year, it seems likely pro-democracy Iraqis will have most of the country pretty well in hand and U.S. troops levels will begin to drop significantly.