Why not? The US ignores treaties whenever it's sufficiently convenient.

But certainly, that is the excuse that will be used.

You mean like when the US refuses to extradite terrorists who bombed commercial airplanes, killing 73 civilians? ( https://news.ycombinator.com/item?id=10471965 ). US said no to two countries extraditing countries - the ones at both ends of the plane trip.

More to the point, none of the national governments particularly care what the EP thinks.