BAGHDAD - Iraq's top Shi'ite, Sunni Arab and Kurdish political leaders announced on Sunday they had reached consensus on some key measures seen as vital to fostering national reconciliation.The agreement by the five leaders was one of the most significant political developments in Iraq for months and was quickly welcomed by the United States, which hopes such moves will ease sectarian violence that has killed tens of thousands.But skeptics will be watching for action amid growing frustration in Washington over the political paralysis that has gripped the government of Shi'ite Prime Minister Nuri al-Maliki.White House spokeswoman Emily Lawrimore congratulated Iraq's...