I have spent considerable time studying rapid collapses of nations or regions. Below is a crude summary of what I have so far assimilated.
What concerns me most about reaching the limits of fiscal and monetary stimulus is the inability to respond in the next crisis as the US Dollar falls, US rates increase, and US stocks plummet. This is the positive feedback loop in a negative cycle that was disrupted in 2007-2008 as the Dollar increased due its reserve currency status. Dollar stability also allowed rates to decrease precipitously and the Fed and Congress to engage in actions that otherwise would not have been available.
What I have not determined is the general chronology of the losses in a death spiral. It seems rates move up, stocks move down, and then confidence erodes and the real damage begins.