If only there was a cost effective and fuel efficient way to get large amounts of cargo across the US... Oh wait, we figured that out 150 years ago at promontory Utah didn't we? What happened with that? Oh yeah, that panama canal thing was cheaper...
Modernization and electrification of rail is the answer to this problem, and quite a few others. Expand that OG rail run through Utah, and add one through the south end of the Rockies from LA to Atlanta. Full double set of electrified rails to run bidirectional traffic coast to coast in a northern and southern corridor.