US President George W. Bush told Americans he would send over 20,000 more US troops to halt Iraq's collapse into civil war but many Iraqis -- and the president's opponents in Congress -- doubted the increase could do much good.
Many saw the surge in troops as a desperate move that would only increase the US' failures in Iraq and could deepen the sectarian divides in the war-fractured country, leading to more bloodshed.
"To step back now would force a collapse of the Iraqi government, tear that country apart and result in mass killings on an unimaginable scale," Bush said in a televised address, responding to calls for him to start a gradual withdrawal.
As voters questioned the value of adding to the 3,000 US troops killed in Iraq, Bush said the Iraqi government must keep promises to rein in militants on all sides to retain US backing -- restating a condition some analysts see as pre-emptively shifting responsibility for any future failure to end bloodshed.
"America's commitment is not open-ended," said Bush, whose own term, indelibly marked by the Iraq war, ends in two years.
"If the Iraqi government does not follow through on its promises it will lose the support of the American people," he said, making a rare acknowledgment of past errors. "The year ahead will demand more patience, sacrifice and resolve."
Iraqi Prime Minister Nuri al-Maliki has vowed to lead the new Baghdad security operation and indicated it would strike not only insurgents from former president Saddam Hussein's once dominant Sunni minority but also militias loyal to fellow Shiites -- a key demand of Washington and Sunnis, who say Iran is backing Shiite gunmen.
Responses to the latest plan highlighted sectarian divides, with Sunnis hoping for the best and many Shiites increasingly resentful of the presence of the US who overthrew Saddam.
Bush renewed complaints about the role of Syria and Shiite Iran in Iraq and US troops raided an Iranian consular office in the Iraqi Kurdish city of Arbil overnight, arresting five Iranians in the second such operation in the past month.
OPPOSITION
Bush's Democratic opponents, now controlling Congress, vowed to resist but are unlikely to block a four-month phased increase.
"We are in a hole in Iraq and the president says that the way out is to dig deeper. Does that make sense?" Democrat Senator Barbara Mikulski said.
"Bush is a prisoner of his own dreams," a leading clerical official for Iraqi Sunnis said.
"The American president is ignoring the dangerous political reality in Iraq," Mohammed Bashar al-Fhaidi told al-Arabiya television, saying Shiite leaders were pursuing a sectarian course to shut out the Sunnis. "Those ruling today have taken the path of exclusion."



