Stability doesn't mean statis. The USA has been remarkably resilient to those minor shocks you listed. It continues to be the most politically stable of all the countries that actually count for anything in international affairs.
If so then what countries in Europe (sans the Balkans) or East Asia do you think are less politically stable than the US?
You're saying "nothing bad will happen because nothing bad has happened so far". There's a first time for everything.