It is sometimes claimed that Afghanistan is the ‘graveyard of empires’ and as a justification of why this is so, one usually hears that this was because no occupying power had ever ‘won’ in Afghanistan, or something similiar. The examples that are normally given to make that case are the Soviet Union and the British Empire. So let’s takle them first.
I realise that is not a scientific work, but nevertheless is quite conclusive as to whether the above claim holds any water. In short, it does not.
a) The Soviet Union (1917-1991)
In an 2009 article on the BBC website named “Reform, Coup and Collapse: The End of the Soviet State”, Professor Archie Brown writes (emphasis mine):
The Soviet Union on the eve of Gorbachev’s perestroika (reconstruction) had serious political and economic problems. Technologically, it was falling behind not only Western countries but also the newly industrialised countries of Asia. Its foreign policy evinced a declining capacity to win friends and influence people. Yet there was no political instability within the country, no unrest, and no crisis. This was not a case of economic and political crisis producing liberalisation and democratisation. Rather, it was liberalisation and democratisation that brought the regime to crisis point. There were five interconnected transformations in the last years of the Soviet Union which are too often conflated into one ‘collapse’ or ‘implosion’. It is especially important to distinguish between the dismantling of the communist system and the disintegration of the Soviet state, for the former preceded the latter by between two and three years.
This view is shared by others. From Wikipedia (emphasis mine):
East-West tensions increased during the first term of U.S. President Ronald Reagan (1981–1985), reaching levels not seen since the 1962 Cuban missile crisis as Reagan increased US military spending to 7% of the GDP. To match the USA’s military buildup, the Soviet Union increased its own military spending to 27% of its GDP and froze production of civilian goods at 1980 levels, causing a sharp economic decline in the already failing Soviet economy. However, it is not clear where the number 27% of the GDP came from. This thesis is not confirmed by the extensive study on the causes of the collapse of the Soviet Union by two prominent economists from the World Bank- William Easterly and Stanley Fisher from the Massachusetts Institute of Technology. “… the study concludes that the increased Soviet defense spending provoked by Mr. Reagan’s policies was not the straw that broke the back of the Evil Empire. The Afghan war and the Soviet response to Mr. Reagan’s Star Wars program caused only a relatively small rise in defense costs. And the defense effort throughout the period from 1960 to 1987 contributed only marginally to economic decline.“
In my view, it’s thus safe to conclude that the Afghanistan War (1979- 1989) was not the cause of the demise of the Soviet Union. It was a combination of factors other than the war that brought the Soviet Union down.