France - and probably not the king per se, but it's hard to tell - irresponsibly borrowed money it could not afford to repay. Lenders - apparently many of them French nobles - irresponsibly offered to lend this money without first checking whether it would be repaid.
In shocking news, irresponsibility is leftist. Too much irresponsibility leads to mass death. Hence, the Terror.
Personnel is policy. France was run by a bunch of mass-murderers, and therefore it ended up in mass murder.
Today France is run by exhausted mass-murderers who can barely bring themselves to lift their knives and axes.