"<span>The United States had a democratic system, and the Soviet Union
had a single-party system" would be the best option since the USSR was
communist.
</span>
it was debt and taxes on the people to pay the debt also some people lost their houses
The valid conclusion about these political phenomena could be that the very strong anti-Vietnam war movement of the American and world's people definitely had an impact on Johnson not running and also somewhat on Nixon (as well as Watergate) and there may have been a backlash against the war mongering of George HW Bush in Iraq and also the brutal invasion of Panama.
