Don Davis does the math on DADT:
[T]he next time someone’s talking about how much national security might be threatened if we change DADT, you can tell them that there’s a cost to national security from keeping DADT as well.
How much of a cost? If you pulled those 115,000 potentially affected troops from the Army, DADT could cost us two Iraqs worth of troops, with 15,000 reinforcements left over, and if it was just the Navy, it could affect enough sailors to crew every aircraft carrier and submarine and 30,000 more besides.
If you removed that many personnel from the Air Force it would affect more people than the entire Air National Guard and seven years’ worth of new pilots combinedor, if you prefer to look at it through the prism of a eagle, globe and anchor, it could be enough LBGT Marines to take and hold darn near anything, from the halls of Montezuma, to at least somewhere near the shores of Tripoli.