I remember when we were all concerned that there was too much hashpower concentrated in China.

China banned mining and the hashpower left.

Now I'm concerned that there's too much hashpower concentrated in the United States.

USA will not ban mining, but they will seek to control it.

Will the miners choose to spend the $$$ to relocate away from this regulatory regime if their mining revenue inside the USA remains profitable?

Some will for ideological reasons, but I think most won't.