Read the whole editorial (caveats and all), but relish the last paragraph.
They're talking about falling casualty numbers:
This doesn't necessarily mean the war is being won. U.S. military commanders have said that no reduction in violence will be sustainable unless Iraqis reach political solutions -- and there has been little progress on that front. Nevertheless, it's looking more and more as though those in and outside of Congress who last month were assailing Gen. Petraeus's credibility and insisting that there was no letup in Iraq's bloodshed were -- to put it simply -- wrong.