With the US death toll in Iraq passing 100 this month and mid-term elections just days away, the Pentagon said Monday the US force in Iraq has grown to 150,000 troops, the biggest it has been since January.
A Pentagon spokesman attributed the growth to overlapping unit rotations, but it came amid surging violence that so far this month has claimed the lives of 103 US troops and many more Iraqis.
"Several units are transitioning out as several are transitioning in," said Lieutenant Colonel Mark Ballesteros, who said that as of Monday the number of US troops in Iraq was 150,000.
A Pentagon official, who asked not to be named, said the US Army's 4th Infantry Division was near the end of its year-long rotation.
US commanders in the past have timed the overlap of troop rotations to increase the US military presence during Iraqi elections and other critical milestones in the political process.
The increase this time follows the Muslim holy month of Ramadan, which US military officials anticipated would bring higher levels of violence, and comes just ahead of the November 7 congressional elections in the United States.
Pentagon officials, echoing Vice President Dick Cheney, have expressed concern in recent days that Al-Qaeda is trying to step up the violence in Iraq to influence the outcome of the US vote.
Cheney warned that deadly violence would plague Iraq for "some considerable period of time" and that it was up to Iraqis to decide how to tackle sectarian militias.
Asked about radical Iraqi cleric Moqtada al-Sadr and his Mahdi Army militia, Cheney told CNBC television that US-led forces had dealt with "the chief bad guy," Saddam Hussein, and that it was now up to Iraqis to handle Sadr.
Sadr "obviously speaks for a significant number of Iraqis, has a strong following. But if anything were to be addressed in that area, it's got to be addressed by the Iraqis themselves," Cheney said in the interview.
"The Iraqis are now the sovereign authority inside Iraq. That's their government. It's their responsibility. They'll have to make those judgments and decisions," he said.
Eric Ruff, the Pentagon press secretary, said he did not know why US troops levels were climbing.
"This is news to me," Ruff told reporters. "Talk to MNF-I (Multi-National Forces-Iraq). That's General Casey's decision."
The increase is noteworthy because US troop strength in Iraq is only 10,000 under the all-time high of about 160,000 reported in January after the Iraqi elections.
It had fallen to as low as 127,000 in June when US commanders still believed they could make troop cuts this year.
In late July, US Defense Secretary Donald Rumsfeld reversed directions and ordered a combat brigade to be extended beyond a year as part of buildup to quell burgeoning sectarian violence in Baghdad.
In mid-September, General John Abizaid, the top US commander in the Middle East, said more than 140,000 troops would be needed through the first six months of 2007 to check the violence.
Since then, US troop levels have oscillated between 142,000 to 147,000, the level it reached last week.
But the stepped-up operations have so far failed to bring the violence under control in Baghdad or stop its spread to other cities, prompting a review of military tactics.
General George Casey, the commander of US forces in Iraq, had said earlier this month that it was an "open question" whether bringing in more troops would have a lasting effect on the violence.
But he left the door open to it last week at a press conference in Baghdad.
"Now, do we need more troops to do that? Maybe," he said. "And as I've said all along, if we do, I will ask for the troops I need, both coalition and Iraqis."
Rumsfeld, however, insisted two days later that Casey's comments had been mischaracterized in press reports.
"Listen, we're in the political season," he said. "People are trying to take what he said and turn it in a way that it plays the way they'd like to see it play."
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