The resistance had support from powerful nations, America among them, with Saudi Arabia and other Islamic nations on the side of the fight against the invaders. The war lasted about 10 years, the losses on both sides were horrific, the nation of Afghanistan was destroyed, The Soviet Union was almost bankrupt and the world did not care. The wars in Afghanistan in the 80's and 90's were part of the struggle for dominance between the East and West. The West thought they had a great victory and now looked to other lands for conquest.
Fast forward to today, President Obama wants to win the war in Afghanistan, not just pacify it, but also win. The problem is that we do not know what a win will look like and any exit strategy is based on knowing when you win and can get the hell out of the "Graveyard of Empires. There is another problem and that is drugs.
Afghanistan produces 90% of opium which is used to make heroin and that is a big problem for any army and especially for an army that is worn out from fighting two wars for the last 8-9 years. We will produce more and more heavy drug addicts for our cities to deal with in the coming years. The army tells us they have not had a major problem with drugs use, but the army lies.