LMAO out of all of this you mention the Chernobyl disaster, which makes me think you learn Soviet history through your Britbong "History" tv series. Maybe next you watch as well a Netflix episode on the Russian Tsar?

Which Soviet leader betrayed the Afghan government and pulled out the military again, led the Socialist Afghanistan to collapse under terrorists?

Which Soviet leader did everything the Americans told him, took IMF loans and put in market elements during an economic stagnation, just like pouring oil into a fire?

Ah, I know, Europeans gave a loud applause after his "performance" and gave that traitor a nobel prize and a passport to live in Germany. You would never admit the bastard caused any of this because you guys suck his D in your history lessons.

followed by many republics declaring independence

you mean re-introduced neofeudalism and cut off partnership with the only country that made sure they have energy, manufacturing and built powerstations, schools and infrastructure with them?

Go ask Moldavia, Kyrgyzstan, Mongolia, Tajikistan, Usbekistan, the Baltics, ... how their new independence feels like? Hell, ask Afghans the last time they flew into space?