Ahhh...I see. It's AOK for you to lump Cimmaron, RIA, Auto Ordnance, Para Ordnance, Regent, ATI and all the rest in with Colt but not ok for me to hang Diamondback and their reputation on Glock.
Speaking to that, I would assert now that polymer is not the issue. Striker fired is it the issue. Modern is not the issue. DAO is not the issue. The real issue for you is brand or weight savings or capacity. Well, tell the sniper with his Barrett he should ditch it for an M4. If he's a good shot, he'll be even better when he sprays and prays because volume makes him more effective.
Why Colt? Production capability. Answered the open call. Parts interchangeability (yes Brent from Colt's Custom Shop has confirmed this). Passed required trials. A Glock can go 100,000 rounds with the same slide? Ask Tuner what his commercial Colts have slung for numbers. If it's built right- and Colt does, it will run right without any undue fuss.
With regard to the Marine 1911 specifically, this is a military firearm. The military does not take pride (as some of you do) in firing 2,000 rounds and leaving them dirty for months. Frankly, that is ignorance on display. It does not run better covered in mud or soot or filled with sand but some boast of showing up unprepared to an actual gunfight? Because a Glock can. Well I suggest never cleaning or lubricating it if it's just as reliable because they aren't bought for looks. How'd that go for the original M16?
Take whatever position you like on the 1911 but I'll ask again: what does your xxx do that a 1911 does not? Weight? Is that a factor for LA SWAT? Ditto on capacity. If an 870 or a 700P is the best tool for the job do you pass based on weight and capacity? And which "reliable" pistol would you choose? H&K? Beretta? XD? S&W? Ruger? Hi Point? Should we like to argue that one next?