The answer is the third one
People were willing to take any ideas and anyone who promised a way out of the economical hole they were rapidly falling into. Obviously, they were used for support during genocides and dictatorships, but were too blind to see what their influence was on things like the Holocaust and Stalin's movement
Checks and balances
supreme court is granted power to overturn congressional laws that violate constitution. the courts however should exercise judicial constrain while doing that, to ensure the do not injure the principle of separation of power. usually they all restrain themselves to comparing whether the new law contradict the establishment clauses which would require a referendum, or the wording and legal process was followed. This ensures congress is checked.
