Your claim was as follows:
"Iran getting, and possibly using, nuclear weapons... or the total economic and strategic collapse of America. Stopping the first will bring about the second."
As shown, your argument was stopping Iran from obtaining a nuclear weapon will bring about the total economic and strategic collapse of America. That is indeed a bold claim -- and remains no less bold even in the face of an all out ground war and nation building project with Iran. Let's look at Iraq -- we spent roughly $1,000,000,000,000 over a decade (roughly) fighting that war. Let's say we fight a war in Iran that costs double what Iraq did -- that is an extra $200,000,000,000 a year. With interests rate where they are -- I think the argument that we could not borrow that and still survive has no real merit.
Yes -- I am interested -- because I am operating under your statement of stopping Iran from getting a nuclear weapon will collapse America. Therefore, I was interested in what you referring to specifically when you mentioned "war". Did you mean an all our ground war? If so, it remains a bold claim that such action will destroy the United States. If you mean limited air strikes -- it becomes an even more bold claim that such action will destroy the country.
Additionally -- you stated that you arrived at the conclusion of a ground war and nation building based on Iraq and Afghanistan -- however then discounted our action in Libya as irrelevant. It is just as plausible if we get involved at all it will be a Libya style operation and not an Iraq style operation.
You asked what I was basing my opinion on that we are not going to have an actual war -- I think I made a pretty good argument. That aside, mission creep or not -- I still fail to see why preventing Iran from obtaining a nuclear weapon will collapse the country? Unless you are taking mission creep to the extreme and creating a scenario in which nuclear war erupts -- I just don't buy it.
Yes -- my conclusion would be different. I would argue such an action would result in a much higher level of American death's than people want to accept, it would take decades and we would not accomplish our goals, it would indeed have a major economic impact -- but I don't think it would come anywhere close to the collapse of the United States.
Because it would cause us to spend more money? That seems to be essentially the argument here. However, with interest rates where they are, it seems unlikely that we could sustain an additional debt load -- while that can obviously change based on many factors -- as of today, that is what I would argue.