BAGHDAD - Signs are emerging that Iraq has reached a turning point. Violence is down, armed extremists are in disarray, government confidence is rising and sectarian communities are gearing up for a battle at the polls rather than slaughter in the streets. Those positive signs are attracting little attention in the United States, where the war-weary public is focused on the American presidential contest and skeptical of talk of success after so many years of unfounded optimism by the war's supporters. Unquestionably, the security and political situation in Iraq is fragile. U.S. commanders warn repeatedly that security gains are reversible....