But does banning something do anything different? Say the USA bans Bitcoin mining due to concerns about its energy use. That doesn’t stop mining in China or elsewhere. On top of that the US now needs to set up an invasive investigation system for enforcing the ban within its own borders.

Applies just as well to YouTube cat videos or any other poor use of energy in the digital realm. Banning YouTube in the USA doesn’t mean that China won’t have data centers streaming cat videos to the USA.

Instead if the USA really was concerned about efficient use of energy and capturing the externalities it could extremely easily (in the scheme of things) work out a better pricing mechanism such as a CO2 tax, and implement it. If it were serious it would also be able to find many willing allies in Europe and elsewhere that would sign up to a multilateral treaty.