I don't think the president ever sent any of us into battle in un-armored HUMVEES. I can't honestly remember and I don't really know since I wasn't here at the time, but I think that story was proven false. As we all know the media loves to get people fired up. THere are several facilities here that handle the up-armoring process. Including a complete Humvee refit facility.
The problem with coming with armor installed on them is that they are extremely top heavy and most of our accidents are happening due to rollovers. Plus, here in Kuwait and just about every other military installation the need for armor is non-existent. The armor adds a ton of weight to the vehicle not only just the metal, but by adding all the 6" thick glass, and A/C systems. The beauty of the Humvee is that it is so easily adaptable to meet other requirements (i.e. ambulance, 4 seater, 2 seater, MP vehicle, gun truck....etc.), but if it already came armored the ability to switch configurations would probably be greatly diminished. As far as the rollovers are concerned the Army is taking active steps to train us how to drive better. I know this because I've been thru the class. It was similar to a police academy EVOC course and besides highly informative it was a whole lot of fun! The showed us how to bring a vehicle back on the road after having drifted off at high speeds without rolling it.
Ok....sorry bout the long post, but I just wanted to put out the info as at least I'm seeing it here. I am by no means an expert on the subject, but probably have a great deal more info on it then some of you.