I have seen you make far more hyperbolic comparisons of the state of the American experiment in self-governance to some truly evil and malevolent regimes from the 1930s at present and in the relatively recent past, rather than the garden-variety incompetence and stupidity of Argentina in the 1980s and 1990s and Greece and Venezuela more recently. To be fair, though, Argentina and Venezuela do have some nasty atrocities to their name from that era. It seems overblown historical comparisons are okay when you do it, but mine -- which are much more tightly focused to what happens when the dole runs dry -- are somehow invalid?
Never ascribe to malice what stupidity explains equally well.
That brings up to why I think it eventually runs dry during a crisis. Any reasonable student of American governance in the past few decades would watch a system the lurches from crisis to crisis rather than proactively trying to address developing problems. I have seen very little interest or action out of state and federal policymakers to address our brewing long-term fiscal imbalances with pensions, funding for various state programs (education, infrastructure, etc.), and federal entitlement programs. If anything, and especially federally where there is no balanced budget amendment, the interest seems to be further profligacy (more tax cuts, more defense spending, multi-trillion dollar "free" XYZ programs, etc.) rather than fixing it up.
Are you right these problems are solvable? Yes, in the strictly mathematical sense, but I do not feel they are solvable in the political sense without outside forces forcing it upon us at the absolute last second. The mathematics and the politics become harder the longer we wait, too. This would have been easier in 2005. The most obvious crises that might develop are a major financial crisis, a run on U.S. debt or the dollar, and perhaps even a loss of reserve currency status. Are those extreme? Yes, sure are, but we are practically inviting them on our current trajectory.
Any charges you make about Republican profligacy and hypocrisy are completely correct, by the way -- and hence I have zero faith, trust, or love for them whatsoever.