Sometimes crises aren’t serial, they all come at once, and they compound each other. From Charles Hugh Smith at dailyreckoning.com:
Back in 2017 when I composed this graphic of overlapping crises, the word polycrisis was not yet in common use. Polycrisis has various definitions, for example: “the simultaneous occurrence of several catastrophic events.”

But this doesn’t explain the truly dangerous dynamic in polycrisis, which is the nonlinear, mutually reinforcing potential of disparate crises to generate effects much larger than the initial causes. This definition is closer to the mark: “Many different problems happening at the same time so that they together have a very big effect.”
Put another way: 1 + 1 + 1 doesn’t generate an effect of 3, it generates an effect of 9.
You’ll notice the crises on my graphic are internal socioeconomic dynamics: state-cartel centralization, demographics, soaring debts, Imperial overreach, technological disruption, disunity in elites and diminishing returns on financial predation.
Many don’t see these as crises; they’re seen as factors, not as potentially catastrophic dynamics. This is the linear analysis: None of these dynamics is actually threatening to the stability of the U.S.
The nonlinear analysis is: Considering each one as a discrete dynamic, that’s true. But these are mutually reinforcing crises because the status quo “solutions” to each one become mutually reinforcing problems which generate much larger effects than most believe possible.