It's totally possible that it has vastly different reasons, but I find the jump to and insistence on "this is it, this must be it, and it's just different elsew

It's totally possible that it has vastly different reasons, but I find the jump to and insistence on "this is it, this must be it, and it's just different elsewhere" to be a bit hastened. It doesn't explain the strong variety in outcome and doesn't seem to apply to other regions. American Exceptionalism is well and good, but it does sound a bit wanted rather than found.