As Obama continues to vote present, it looks like another pro-American Middle East regime is about to fall.\r\nTens of thousands of protesters rallied in Sanaa today.\r\n\r\n\r\nThe top Yemeni tribal chiefs joined the opposition today against the pro-American president.\r\nThe Daily Times reported:\r\nPressure on Ali Abdullah Saleh to resign intensified on Saturday when the leaders of two of Yemen\u2019s most important tribes abandoned the president and joined the anti-regime movement. The news came as an official denied reports that police killed four people on Friday in an assault on an anti-government protest in Aden, blaming a southern secessionist group for the attack. \r\n\r\nPowerful tribal leaders, including those of the Hashid and Baqil, pledged to join protests against Saleh at a gathering north of the capital, a tribal source told AFP. \u201cI have announced my resignation from the General People\u2019s Congress in protest at the repression of peaceful demonstrators in Sanaa, Taez and Aden,\u201d Hashid tribal chief Sheikh Hussein bin Abdullah al-Ahmar was quoted as saying, in reference to the ruling party. The Hashids are considered Yemen\u2019s most powerful tribal confederation and include nine clans, among them the Sanhan, long a bulwark of Saleh\u2019s regime. \r\n\r\nThe announcement was warmly received by a large crowd of tribesmen, including members of Yemen\u2019s second largest tribe, the Baqil, who gathered for the meeting, according to the tribal source. The two tribes announced they would support the popular uprising against Saleh, who has refused to step down after three decades in power, to chants of \u201cthe people want the fall of the regime!\u201d For the record... Al-Qaeda in Yemen is now the biggest threat.