Muggles in question limited to UK, not the whole world. Muggles in HP world posed zero threat to him. Competence level barring less than zero. Spells that are 'assumed' by fans, that word keeps getting thrown out everywhere.
@lordofallhumans:Nor does it give license to keep it the same, because the old argument is done. They OP did not exclude any other fiction, only mentions 'US Military' to give the U.S. a win because you couldn't think around Voldemort (that would have taken creativity).