If you ask most Americans what the beginning of the end of the Soviet Union was, they will say “the fall of the Berlin Wall” but something else happened a couple months earlier, something called the Baltic Way.
It was one of the largest peaceful protests in history, which was a chain of people holding hands from Tallinn, through Riga, to Vilnius (around 400 miles long) and singing patriotic songs. 1 in 4 people in all 3 countries participated, small children, old people, everyone.
And that gave Gorbachev a choice, he could send the military to crack down on those peacefully protesting children and old people, with live rounds and mass arrests as the Soviet Union responded to the Prague Spring.
Or he could do what he did, turn the tanks around and let the protest go on. Later leading to Lithuania, very quickly followed by Latvia and Estonia to be the first SSR’s to declare independence.
When Putin says “The breakup of the Soviet Union was the greatest geopolitical tragedy of the 20th century” that is what he means.
He means that he believes that the fact Gorbachev did not gun down those peaceful protesters and bring the Baltic states in line was a worse tragedy than the Holocaust.
Think about what that might mean about Putin’s respect for the sovereignty of all Russia’s neighbors
Think about what that might mean if Putin were to gain control over one of those “rebellious peoples/cultures” again.