I think we are winning in Iraq. I've consistenly stated that our military force cannot win on their own, but can only provide a shield behind which the Iraqis can organize their own society, government, and security forces. Once mature, these factors will combine to defeat the internal enemies of the Iraqi government.
I believe that tracking statistics such as US monthly casualties or attacks per day to see if we are winning is misleading. These statistics track intensity of battle and do not measure whether we are winning the war.
In World War II, I dare say that our casualties and combat contacts would have shown levels getting higher every month starting in 1942, picking up with the counter-offensive in the Pacific and the North Africa and Italy operations in 1943, and accelerating through 1944 operations in both theaters that closed in on the enemy's homelands through 1945, right until the numbers dropped off to near zero after the formal surrenders of Germany in May 1945 and Japan in September 1945.
The metric of winning was the advancing forces of the US and the Allies as we drove toward Berlin and Tokyo. The metric was easily grasped by anybody just by looking at a map. But divorced from the map, the high levels of casualties and combat that actually increased from year to year--until the final victory--would have indicated quagmire or even defeat.
So in Iraq, while final victory will see attacks and casualties for all forces--Iraqi and US--dwindle, until then, these two metrics may very well remain high. But these are statistics of battle--not victory metrics.
Behind the shield of US forces, the real metrics of progress in society, the economy, government, and security advance. The population remains optimistic about the future; and Sunnis start to abandon resistance. The economy grows and consumer goods fly out the doors. Elections are held with people voting for officials and a constitution; and Iraqis long excluded from governing learn the ropes in the executive branch and courts. Iraqi police and troops increase in numbers and training, taking over more of the security burden; and the enemy is atomized, reduced to terrorism and kidnapping rather than proper insurgency.
These are the real metrics of success. With these metrics firmly trending toward our victory, we will win. And then the statistics of combat and casualties will trail off--either slowly or perhaps dramatically, as I suspect--as the result of our victory.