Answer:
The USSR (Soviet Union) lost the Cold War due to a couple of reasons:
1) Economic stance: The Command Economy created by Karl Marx, and used by the USSR & other communist countries, only work when implemented correctly, and in which no politician is trying to push their own agenda. Of course, this does not work in real life, and so the Command Economy was bound to fall apart soon.
2) Military stance: The USSR was able to help support many other communist countries, but they failed to take account that the US would also do the same. They suffered many defeats & failures, including the failure of taking the Korean Peninsula, the failure to stomp out the rebellion of Afghanistan, etc. These led to the destruction of the military, and the weakening of the USSR.
3) Political Stance: The USSR was built as a Totalitarian Government in the guise of giving the people more equal power (They get equal power, which is no power). This creates a strong arm government, however, when the leader dies/replaced, the change could be extremely different, and can lead to the destruction of the current government, and even the current government structure. The Totalitarian Government does not take this into account, and is why it would generally fail within one or two leaders.
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