By keeping some troops a few months longer in Iraq, and bring in a few  thousand more, the United States is increasing its troop strength by about 12,000. This will last through the elections at the end of January. The Sunni Arab terrorists are expected to make a major effort to stop those elections. When the Sunni Arabs fail to stop the elections, they will suffer another major defeat as they did in Fallujah. The Sunni Arabs have long been split, and not being able to halt the elections further isolates the Sunni Arab diehards. Having more troops available for the next two months makes it possible to give the Sunni Arabs are sharper, and quicker defeat.