[HorseSoldier]

To me it seems pretty obvious that whatever nuclear ordnance any of the various US governments still have access to (and you are correct, there are brief references to them in Howling Wilderness) by the time of the Mexican invasion was not available . . . because if it was, Mexico City and assorted points north of there and south of the Rio Grande would have been vaporized. What, exactly, the lack of a strategic campaign against Mexico indicates is open for conjecture, but it certainly points to some significant problem with the remaining US nuclear inventory (be it political will, communications failures, or possibly a fear of additional launches being detected by the Soviets and somehow triggering a general, city busting, exchange . . . or some other reason).

Now, as to CENTCOM or USAREUR or anyone else sweeping into Texas and sweeping the Mexicans out . . . again, see previous comments about MilGov, CivGov, and everyone else (Mexicans and Soviets in Texas included) being unable to reliably feed themselves or guarantee the safety of their own internal lines of communication. That (plus a whole slew of other problems) is going to combine to mean there's appreciably little industrial economy to support military efforts. After the smash up in Europe with NATO's summer offensive, circa 2000, everybody except the French seem to be so exhausted that bandit suppression is about the limits of what they can manage. Which makes sense trying to get by on a scavenger economy with dwindling resources of pre-war materiel and little to no new production taking place.

And sure as heck CENTCOM would do it otherwise - two paratroop divisions, two Marine divisions, and a Mech division against what I just described? And the payoff is that MilGov gets to uncap all those oil wells and put them to use with an operating refinery?

I think you're grossly underestimating the kind of manpower necessary to just establish and maintain some semblance of control over an area as blasted as the post-nuke US (and elsewhere). I just got back from Afghanistan where about that much manpower backed by every high tech toy we can dream up can't reliably keep the roads open to civilian and military traffic.

And unlike T2K combatants, we didn't have to worry about where our next meal was coming from, didn't have to worry about a breakdown of the medical system meaning that a big chunk of us would die from camp diseases, where out resupply of ammunition/food/fuel/etc would come from (and when it would get there), etc. Honestly, the war in Afghanistan is probably a cake walk compared to what you're talking about.

Actually, if you take the Texas scenario and completely delete the Mexican military and Soviets from the equation, it's quite possibly more than CENTCOM's surviving personnel and resources could handle just to restore and maintain stability in Texas in the middle of a humanitarian debacle and the developing ethnic war between Mexican refugees, Mexican-American communities, and Anglos that GDW talks about in Red Star, Lone Star. We're literally done that mission more than once in real life in the last couple decades, and I think if you asked most staff officers how they'd manage a peace enforcement mission in a country the size of Texas with multiple armed factions -- and do it without air support or any aviation to speak of, shaky communications, no RSTA besides what truck or horse mobile cav can do for you, extremely limited armor and fire support, extremely limited motor transport, and both very limited and very shaky logistics . . . there would not be a lot of optimism in the room.

its not like they were starving in Europe - they had cantonments and were doing ok. In fact thats why several didnt leave.

Units in cantonment (Europe and elsewhere) weren't starving to death circa 2000 for a couple reasons. First, a lot of them had already died from starvation or starvation/malnutrition related diseases and problems in previous winters. (Military personnel deaths were probably more about sustained malnutrition and its consequences than starvation itself, if only because they had guns and tanks and such to ensure that if anyone got food they did). Second, units were eking by circa 2000 by converting their manpower strength to agricultural laborers and were unable to undertake significant military action if it conflicted with planting season or the harvest. Even then, I don't think anybody in T2K's Y2K is doing ok -- at best they're one bad harvest or other disaster away from another winter where old folks and children don't make it and some people end up eating their shoe leather.