Besides military, money also shapes Afghan troop options

While President Barack Obama's decision about sending more troops to Afghanistan is primarily a military one, it also has substantial budget implications that are adding pressure to limit the commitment, senior administration officials say.

The latest government estimates place the cost of adding 40,000 U.S. troops and sharply expanding the Afghan security forces, as favored by Gen. Stanley A. McChrystal, the top U.S. and allied commander in Afghanistan, at $40 billion to $54 billion a year, the officials said.

Even if fewer troops are sent, or their mission is modified, the rough formula used by the White House, of about $1 million per soldier a year, appears almost constant; in 2006, congressional researchers had estimated the per soldier cost to be $390,000.

So even if Obama opts for a lower troop commitment, Afghanistan's new costs could wash out the projected $26 billion expected to be saved in 2010 from withdrawing troops from Iraq. And the overall military budget could rise to as much as $734 billion, or 10 percent more than the peak under the Bush administration.

Such an escalation in military spending would be a politically volatile issue for Obama at a time when the government budget deficit is soaring, the economy is weak and he is trying to pass a costly health care plan.

Senior members of the House Appropriations Committee have already expressed reservations about the potential long-term costs of expanding the war in Afghanistan. And Obama could find it difficult to win approval for the additional spending in Congress, where he would have to depend on Republicans to counter defections from liberal Democrats.

One senior administration official, who requested anonymity to discuss the details of confidential deliberations, said these concerns had added to the president's insistence at a White House meeting on Wednesday that each option include the quickest exit strategy.

"The president focused a lot on ensuring that we were asking the difficult questions about getting to an end game here," the official said. "He knows we cannot sustain this indefinitely."