I didn't really mean to start a debate about Bases and railways - it was more of a rhetorical question. I know nothing about military transportation and logistics, but it strikes me that when you have to move a lot of stuff, heavy stuff, or a lot of heavy stuff, in a halfways expeditious manner, doing it in ones-and-twos on truck or in an aircraft strikes me as a tad inefficient. I also don't know where lots of big heavy things are. Also, the concept of 'nearby' may have it's own limitations. Beyond the presence of loading facilities for 'big heavy things' and the quality (weight limitations) of a local line, having to schlepp something onto a truck only to off-load it to reload it onto rail seems rather inefficient.
Maybe it's not that big an issue.