Many people give credit to Ronald Reagan and his actions during his Presidency for expediting the fall of the Soviet Union. But many also fail to recognize the rapid progress that was being achieved during the Nixon Presidency in thawing relations during the Cold War. His going to China helped to loosen up the Soviets to negotiations, and Nixon even visited the Kremlin (the first President to do so) and it appeared for a time that the Cold War may have a light at the end of the tunnel.
If Nixon was not tainted by Watergate, which could easily be avoided by avoiding the release of the Pentagon Papers earlier in his Presidency, how do you think his foreign policy would have proceeded? especially with the Soviet Union.
Could the Cold War have been brought to an end without the Soviet Union collapsing? How would North and South Vietnam proceeded with a still powerful Nixon in the White House?