You all should be glad there's only a passing interest (at best) in soccer in the US. If the public really latched onto it like American Football or Baseball the teams would have all the money they'd need to scoop up the best players in the world (and you'd be left with the dregs).
You can't buy people to play for the national teams, though. Also I'm not really sure the US teams would so quickly get as much money as some of the richer European clubs. You probably don't know how much money clubs like Manchester Utd., Barcelona, Real, Inter, Chelsea, Arsenal, Milan and the like have exactly.