Hmm - rebuild America - sounds like code for spending $10T to rebuild $1T worth of infrastructure? But at least we'll save all those $trillions needed for airports since air travel will be phased out.
I can't resist doing a bit of parsing. "Rebuild" means that it was built once, but now we need to build it again to make it as good as it was the first time. So his slogan could safely be rephrased as "Make America good again"? I think that has a much better ring to it.