This happened in particle physics in the 90s. What you'll see is Europeans being hired in 20 years to fill all the positions, when the continent has LHC and the US doesn't. I think there was also a smaller, but also very significant setback at the start of the Bush Jr. era. We're stuck in a vicious cycle where every cancer researcher votes for the candidate they don't think will fire them, and then the other candidate tries to fire everyone who they know didn't vote for them.