No real need for us to make economic or investment preparations for that eventuality. It does us no good in the life we do have to say, "Well, I can't invest in the US because in the worst case, non of our secret weapons function fully, Russia blows us away, and all my real estate and manufacturing investments go up in smoke." We'd sit around never improving anything, because it will all go away in the worst case.

Best to assume it won't go away because we won't go to war with Russia or China, (or even maybe the EU nowadays? Who knows?). Anyway, we should make investment decisions on the "we aren't gonna go to war" basis. If war happens, well, we're dead and all the investments are destroyed anyway so.. yeah.. nothing you can do. Can't even get out of the continental US in 15 minutes, so you can't even save yourself let alone your investments.