1. Ukraine, the largest granary in Europe, became a burden because Ukraine was forced to supply food to Russian cities such as Moscow and St. Petersburg indefinitely during the Soviet period. The most tragic incident was that Ukraine's own food was misappropriated by the then Soviet government, resulting in130,000 Ukrainian people starving to death.
2. Chechnya and other ethnic minorities left the Soviet Union for two main reasons.
First, the vanguard troops of the Soviet Union during World War II were all ethnic minorities, that is, cannon fodder. It has aroused the dissatisfaction of many ethnic minorities.
Second, during Stalin's period, almost all ethnic minority residents in Chechnya or Caucasus were forcibly moved to Siberia or desolate Stan (Kazakhstan, Kyrgyzstan, Turkmenistan. . . . On the grounds of endangering national security, a large number of poor people died in exile. After Gorbachev came to power, Chechens returned to their hometown, but there were already a large number of Russian residents living in their hometown, so the contradiction was not solved, but the hatred was intensified.
3. Belarus, Georgia, and all kinds of Stan left because resources and energy were used by the Soviet Union for free, were not treated equally, and were often despised, disrespected, and persecuted. This is the reason why the ultra-nationalism of Russian skinheads prevailed (their slogan is "Russia belongs only to Russians"). Russians only appreciate themselves in their bones.
There are many details, and my explanation is not comprehensive, which may not prove anything. But these are all facts that have happened or are happening.