It's the same thing that happened with jazz - invented by Americans but subsequently ignored by the American population and embraced in Europe and Asia.
Black Americans.
House was invented by DJ Ron Hardy. A Blackman.
Some Blackmans (Saunderson, Mills and Bailly) from detroit mixed Ron's groove with Kraftwork and Techno was born.
Maybe Americans are just Racists.
why is hip hop that big in the states then, its blackmusic aswell