To clear some things up...
The DHS contract was split between SIG and HK. Agencies under DHS can opt for either. The USCG bought 12,000 P229Rs in .40 caliber. Pistols under the DHS deal are the HK P2000, P2000SK, and USPc (all w LEM) in 9/40/357. The SIGs are the P239DAO, P226R-DAK, and P229R-DAK in 9/40. DHS already has options on SIG 357s through previous deals w subordinate agencies. Agencies under DHS might buy all SIGs, all HKs, mix it up, or none at all. DHS has previous deals in place w Glock too, and CBP (Customs and Border Protection) has been issuing Glock 9s since Oct of 2003, still is AFAIK.
The Army Ruger/SIG deal is a whole 'nother enchilada... they just wanted 10,000 pistols cheap and fast. Emphasis on the cheap and fast since no testing was done and they split it 5,000 each to get em to Iraq in a hurry. The SIG they got was the sig pro w Picatinny rail.
Why look for a new gun now? Cuzz at the normal usage rate of 200 rnds per year, and a contract specified service life of 5000 rounds, the M9 is about due (5000/200=25, 1985+25=2010). The local base has on avg over 30,000 rounds through it's M9s for example. We may have plenty in storage, but we had plenty of 1911s in storage in 1985 too...
The Army's "market survey" last Oct 04 for the Future Handgun System (FHS) makes it clear they would like a one gun fits all solution as much as possible:
"The focus of the future handgun system (FHS) is to augment close quarters battle and security/force protection operations, and to offer significant improvements over the current handgun system. Additionally, the FHS will support the requirement for a personal defense weapon."
Lottsa luck.
The draft specs for the SOF combat pistol head that off at the pass by asking for a 45 ACP w a "consistent trigger pull" up front. As of Jan 05 they also want a "modular action mechanism that allows reconfiguration at the unit level w/o modification to the weapon's major assemblies" and a trigger that will "reset after being released, even if the pistol is not fired" and "the operator shall be capable of pulling the trigger, w/o moving the firing grip" (both bad news for Glock and SA/HS/XD type guns). They want a service life of at least 20,000 rounds this time and a MRBS of 2000 - 5000, 1000 w suppressor attached... yada, yada, yada...I wish they had thrown self-cleaning in there too.
The FN FNP and HK USP/P2000 pistols are closest to meeting all the specs. FN already has scored points w the SCAR (special forces combat assault rifle) contract, a FNC carbine in regular (5.56) and extra crispy (7.62). FN needs to whip up a FNP45 IMO.
I've shot the USP/P2000 and FNP, like the FNP best. YMMV.
Now tell me why the M1911A1, M14, and M3A1 wouldn't work as well today as they ever did, maybe even better than some of the new stuff?