Question

In 1991 the Soviet Union collapsed MAINLY because

Answer 1

they were running out of resources from war and corruption

Answer 2

By 1991, more than 70 years of political oppression, mass murder and dictate from one party, all of which are a all too common characteristic of communist states, the Soviet Union was no longer capable to exert power over their member states and their Eastern and Central European satellites (which have went through more or less peaceful separation from the "Eastern block" by 1991). Economically deprived due to mismanagement and corruption, member states started seceding. In 1991, a coup d'etat was attempted by communist hardliners and failed, which was arguably the final blow to the monstrosity known as the Soviet Union. It was officially dissolved a few days after.