Why did the Soviet Union collapse?

In this video I explain the factors that contributed to the collapse of the Soviet Union Works Cited: (1) Grachev, A. S. Final Days: The inside Story of the Collapse of the Soviet Union. Boulder, CO: Westview Press, 1995. (2) Reuveny, Rafael, and Prakash Aseem. "The Afghanistan War and the Breakdown of the Soviet Union." Review of International Studies 25, no. 4 (1999): 693-708. (3) Suny, Ronald Grigor. The Revenge of the Past: Nationalism, Revolution, and the Collapse of the Soviet Union. Stanford, CA: Stanford University Press, 1993. (4) BERGSON, ABRAM. "Soviet Economic Slowdown." Harvard International Review 4, no. 3 (1981): 3-32. (5) Easterly, William, and Fischer Stanley. "The Soviet Economic Decline." The World Bank Economic Review 9, no. 3 (1995): 341-71. Gatrell, Peter. "Feet of Clay? The Soviet Economic Giant in Recent Historiography." The Historical Journal 49, no. 1 (2006): 299-315.