From Military.com, Feb. 1:

President Bush and his new military chiefs have been saying for nearly a month that they would "surge" an additional 21,500 troops to Iraq, in a last, grand push to quell the violence in Baghdad and in Anbar Province. But a new study by the non-partisan Congressional Budget Office says the real troop increase could be as high as 48,000 -- more than double the number the President initially said.

That's because the combat units that President Bush wants to send into hostile areas need to be backed up by support troops, "including personnel to staff headquarters, serve as military police, and provide communications, contracting, engineering, intelligence, medical, and other services," the CBO notes:

Over the past few years , DoD’s practice has been to deploy a total of about 9,500 personnel per combat brigade to the Iraq theater, including about 4,000 combat troops and about 5,500 supporting troops.

DoD has not yet indicated which support units will be deployed along with the added combat forces, or how many additional troops will be involved. Army and DoD officials have indicated that it will be both possible and desirable to deploy fewer additional support units than historical practice would indicate. CBO expects that, even if the additional brigades required fewer support units than historical practice suggests, those units would still represent a significant additional number of military personnel.

To reflect some of the uncertainty about the number of support troops, CBO developed its estimates on the basis of two alternative assumptions. In one scenario, CBO assumed that additional support troops would be deployed in the same proportion to combat troops that currently exists in Iraq. That approach would require about 28,000 support troops in addition to the 20,000 combat troops -- a total of 48,000. CBO also presents an alternative scenario that would include a smaller number of support personnel -- about 3,000 per combat brigade -- totaling about 15,000 support personnel and bringing the total additional forces to about 35,000.

According to the study, the costs for the "surge" would also be dramatically different than the President says. While the White House has estimated a troop escalation would require about $5.6 billion in additional funding, the CBO now "estimates that costs would range from $9 billion to $13 billion for a four-month deployment and from $20 billion to $27 billion for a 12-month deployment, depending upon the total number of troops deployed." (There's a more detailed analysis of the numbers on pages 3 and 4 of the study.)

As we noted more than two years ago, they've been dangling troop reductions like a carrot since the "mission accomplished" moment of May 2003. Now things have gotten so bad that they've had to abandon the carrot—but still fudge the numbers and resort to euphemisms like "surge" (much more reassuring than "escalation"). Is there any light at the end of this tunnel, to use the Vietnam-era analogy?

See our last post on Iraq and the "surge".