U.S. law limits how much reliance the President can put on the National Guard and Reserves in a conflict short of a World War II class one. This conflict has nearly tapped out
this source of personnel:
While the United States has 1.2 million military reservists, only 700,000 of them are in the army, which is the service most in demand. Not all of these army reservists have skills required in Iraq and Afghanistan. . . . By law (10 USC 12302), the president can declare a partial mobilization (which he has done) that allows putting reserve (including the National Guard) troops on active duty for up to 24 months. . . . Most reserve and National Guard troops have reached their limit. For example, the Army with 700,000 reserve troops*, has fewer than 100,000 people left who can be activated.
The number of reserve and national guard troops on active duty peaked at 220,000 and has now fallen to 138,000. Thus, reserves and national guard troops can only be activated for about one more tour of duty, and then only at about half the peak Iraq War levels. A tour of duty in Iraq is typically 7-12 months
, depending on the service (longer in the Army, shorter in the Marines). After that, President Bush will have to rely entirely on active duty forces or get Congressional approval for more troops. The real crunch will hit right around the 2006 campaign season.
Congress has already gone on record almost unanimously against a draft just before the 2004 election, and has shown great reluctance to make even modest increases in active duty military personnel numbers, let alone a 100-200 thousand person increase in the Army's ranks. The Army, in fact, is having a hard time finding enough people to fill its currently authorized force levels. It expects to be 12,000 recruits short in 2005.
Something has to give, soon.
* While the language in the quoted material doesn't make it clear, the 700,000 figure refers to Army Reserve and Army National Guard totals combined. The number of troops in each component are listed on this page of dkospedia.