Again every one is giving more importance to money then the suffering of the Afghans.
And Brit Coalition forces have been more brutal and killed a lot more then Taliban. The life in Afghanistan cannot be compared with the ones in developed countries. I admit that there may be warlords and leaders who are making the life of Afghans miserable(not just women and children) but again it is the right and obligation of Afghans to decide if they want to live with these warlords or not. Since 1979 they are continuously at a state of war and they are atlest 2 centuries behind the developed nations. killing them is not the answer as the ones responsible for their misery and backwardness must pay to allow them to develop their country but instead our governments are paying and supporting these warlords to assist them for their own causes and not for the development of the poor people of Afghanistan. Even Karzai is a paid puppet protected by US private forces(DynCorp to be precise) to work for the interests of US and not the Afghans.
If you want to account for the 300 billion, check the accounts of these warlords and you will find your money. I doubt that even a single penny was paid to the poor people.