>>14135191All of the most important are in the mountain west (mountain states, interior Pacific coast states, Texas, and Alaska. This is due to several factors but the most critically important is geography (topography, climate, geographic location relative to important infrastructure and other countries etc).
Several examples, can read basic info on wikipedia.
1. Davis Monthan AFB AMARG Arizona (desert climate, exceptionally low erosion forces at work, proximity to US border region a leading aviation and missile industry city [Tucson, AZ] interstate and railway corridors, houses over 3,000 active and de-active US military aircraft and nearby in Tucson Raytheon makes a host of modern US missiles and guided munitions associated bombing ranges aren't far off either)
2. Sierra Army Depot California (extreme desert climate, away from vulnerable coastal region in the interior yet close enough to infrastructure to mobilize resources rapidly, houses thousands of US Army tanks and vehicles)
3. Kirtland AFB New Mexico (again desert climate, deep inland location, in this case even lower population density but still has infrastructure connections via interstate, possibly houses as much as 2,000 active nuclear weapons)
4. Cheyenne Mountain Complex Colorado (mountain installation providing command and control to numerous US space and air assets)
5. Nuclear launch facilities in the great plains region with attached or nearby major air bases, South Dakota, North Dakota, Nebraska, Wyoming, and Montana. (near the geographic center of the continent, isolated, low population density)
6. Fort Greely Alaska (US missile interception installation with nearby associated radar providing coverage over the whole Pacific ocean, other associated airbases in Fairbanks and Anchorage regions)
7. Fort Bliss region TX-NM (desert climate, access to nearby industrial area and city as well as interstate corridors, bombing and artillery and missile test ranges, and near the border region)