There are officially 195 countries in the world recognized by the United Nations (193 member states and two observer states: Vatican City and Palestine). Consequently, there are roughly 195 distinct nationalities associated with these sovereign states.
And in the United States of America, ~195 of all of those distinct nationalities are present in this country, natural-born or immigrant (regardless of status).
And, of the approximately 7,168 known living languages in the world today, somewhere in America most of those languages will be spoken today.
You're 100% correct, Moder8... The lifeblood of America is immigration..
Nuclear-war-proof survival bunkers
The only thing these people will have, after the nuclear war, is a slow (or fast) death in their nuclear-war-proof survival bunkers.
Slow, as there's no way a multi-millionaire/billionaire will have enough manpower to keep such a bunker running for very long; or,
Fast, if those who the multi-millionaires/billionaires hire instead turn their weapons on their "employers," and take it all for themselves.