An interim report from Rand Beers and Ilan Goldenberg details the costs of escalation (600 dead soldiers; 3,000 wounded; $10 billion per month) before concluding:
Unfortunately, this investment has yielded no real progress. The President’s policies have failed to bring security to Iraq. The country remains mired in multiple civil wars with Sunnis fighting Shi’a, Sunnis fighting each other in Anbar and Diyala, Shi’a fighting each other in the South, and Kurds fighting Sunnis around Kirkuk and Mosul. Iraqi Security Forces, who are supposed to be taking on greater responsibilities, cannot be trusted to enforce the law fairly, and all too often turn on American troops or take part in sectarian violence. Meanwhile, the Iraqi government is teetering on the verge of collapse. One third of the Cabinet, including the major Sunni party as well as the party of Muqtada Al Sadr, is currently boycotting the government. Without the participation of these groups there can be no meaningful progress on any of the key political benchmarks including the oil law, de-Baathification, or amending the constitution.
See the full report in PDF. What Beers and Goldenberg don't seem to consider, however, is that by simply adopting new, different benchmarks we can achieve Success By Definition, the ultimate accomplishment of any armed force.