Canadians, Mexicans and Europeans can make a massive impact to America's tourism industry if we all collectively decide to stop visiting

Already decided not to! There would have been 3-4 of us spending 2 weeks and a combined 10-12k euro in total probably (although flights would have been a European airline)…I have no intention of spending my summer holiday in an ICE detention camp!

Issue proper travel advisories, blocking insurance for people visiting the states. An official travel advisory would cut tourist volumes down by quite a bit. No one wants to pay US medical rates.

Very unlikely to happen though.