In Afghanistan: Two Hundred Years of British, Russian and American Occupation
By David Loyn
Afghanistan is a country mostly of deserts and mountains, a very small part of the land is irrigable agricultural land. And all invaders have found it a really difficult place to hold. The British general, famous General Wellington at the beginning of the 19th century, said a small army would not be not be able to hold the country and a large army would starve. http://www.npr.org/templates/transcript/transcript.php?storyId=113582498
"There are two key things. Firstly, the terrain is extremely hostile to armies who don’t have very good logistics and supply routes and all the rest of it. Even nowadays, U.S. forces are finding it difficult to keep supplies up despite all the technology available, and despite massive air superiority. This is a country of deserts and mountains and it naturally lends itself to people who can live in that environment. In particular, the eastern mountain range, the Northwest Frontier, is 400 miles long and 200 miles wide, with high peaks going up to about 15,000 feet and only three crossing points, the most famous of which is the Khyber Pass. That’s the place where the British found a huge problem trying to fight against Afghanistan in the 19th century, and where now the Pakistani army is trying to take on the Taliban and finding it a difficult fight."
