This is the only feasible strategy of the three, and still not without risk. Simply put, it's a bit of a strain for us to drop another 30,000 troops anywhere right now, and there's no guarentee this will dent the problem. If this falls though, it's going to strengthen the perception that we're in a fight we can't win.
Another strategy would redirect the U.S. military away from the internal strife to focus mainly on hunting terrorists affiliated with al-Qaeda.
Letting the country fall apart to hunt al-Qa'ida is dumb on two levels. First, we need specialized units and resources to hunt AQI, and they're already comitted. It just takes time to gather the intelligence needed to find them. Putting more troops on the problem isn't going to help noticibly, but it will allow chaos to spread elsewhere. Not a good trade.
And the third would concentrate political attention on supporting the majority Shiites and abandon U.S. efforts to reach out to Sunni insurgents.
Giving the Shiites the standing to go Rwandan on the Sunnis in 2007. Also not a great plan. This would destabilize the country and soon after, the region, faster than anything we could do. All for the benefit of Iranian proxies and Iran itself.
Letting the country fall apart to hunt al-Qa'ida is dumb on two levels. First, we need specialized units and resources to hunt AQI, and they're already comitted. It just takes time to gather the intelligence needed to find them. Putting more troops on the problem isn't going to help noticibly, but it will allow chaos to spread elsewhere. Not a good trade.
I should point out that this is likely a code for saying "Cut back on all missions except hunt al-Qa'ida", making it the cute sister of 'Cut and Run'. We can't really beef up the hunt AQ mission, since it's a very specialized task that takes specialized troops and resources, and they're already in the game. Cutting down on everything else would keep the popular part of the war up and running, and let everything else go to hell.
That, by itself, is a remarkably stupid plan. If you instead make it a "Hunt al-Qa'ida, turn all other missions into 'train Iraqis'", then the plan has some merit, and would produce good long term results for us.