That's the verdict of the experts at StrategyPage.com. The analysis is in line with most all media reports coming out of Iraq over the last couple of weeks as the tide of press coverage turns cautiously positive on the news that the violence in Iraq has been cut in most places by up to 2/3 what it was earlier in the year:

While much was made of the “surge offensive” of the last six months, this was not the key factor in reducing American casualties. The big deal was the collapse of the Sunni Arab resistance, and this has been building for over a year. Half the Sunni Arab population has already fled their homes, and many of those who haven’t, are planning to. A major source of income in the Sunni Arab community is cash paid to those who build and place roadside bombs (which account for about half of American casualties.) This effort, paid for by wealthy Sunni Arabs outside Iraq, and former supporters (and cronies) of Saddam, peaked late last year. The cash, and bomb making supplies, are drying up, while those eager to do get involved are fewer in number. That’s because it’s gotten a lot more dangerous to do that sort of thing. U.S. and Iraqi troops have much more effective techniques for catching the bombers in the act. The bombers have demanded more money, or simply gotten out of the business. The number of bombs placed, and attacks in general, have plunged since last Summer, and along with it, U.S. casualty rates.

Attacks have gone down to a third of the level a year ago. In Anbar province (western Iraq) and Baghdad, where most American casualties take place, this has meant a decline from over 1,400 attacks a month late last year, to about 500 in the past month. “Attacks” include all manner of hostile, and harmful, activities. Each time someone fires a rifle or RPG at U.S. or Iraqi forces, it is considered an attack. So is the use of grenades, mortars or rockets. If a roadside bomb, or other type of IED, is encountered, even if it doesn’t go off, it is considered an attack. The Sunni (and some Shia) Arab terrorists are still setting up roadside bombs, but the number has gone down from nearly 2,000 a month, to about 600. Most are found and destroyed before they can hurt U.S. or Iraqi forces.