BTW, Alois saw that America would lose all it's territories and no longer be a super-power nation.
Do you have that quote? I'm not aware of the US having too many significant "territories" per se, unless he means the "influence" the US exerts over the European nations and NATO.
Economically the US would be entirely crushed ... until it had the time to build out its manufacturing again. US does have significant natural resources where it could rebuild but by that time Europe under the Great Monarch and the Holy Pope would likely assume leadership in the world. And I get the impression that the US too would convert to Catholicism (not form Irlmaier but from other Catholic prophecy stating that the entire world would convert), so why would the US then ever exert itself over the rest of the world at that point? Those imperialistic policies really have been more at the service of the Jєωιѕн agenda than in US interests.
Of course, a Yellowstone eruption would in fact negate my observation above regarding US natural resources, as much of it, especially good farmland, would be neutralized in the short term. Longer term, of course, the volcanic ash would render the ground very fertile, but in the short term there would be serious issues, as much of the farm equipment would be destroyed by the ash fallout.