Child Soldiers in Afghanistan

I read an article from the UN Office for the Coordination of Humanitarian Affairs about the child soldiers in Afghanistan. Even though the Taliban was kicked out of Afghanistan by the USA, there are still military groups that are fighting to get power of Afghanistan. Those military groups are recruiting children to fight their battles. Many kids in Afghanistan have to join the armies to get money for thier families. They get paid for fighting wars. The article says "The reasons are obvious: children are cheaper to employ, slow to question authority and often quick to prove themselves in Afghanistan's gun-dominated macho society." That is why there are so many child soldiers in Afghanistan, there are 8,000 child soldiers there when the United Nations last did a check. The reason there are child soldiers in Afghanistan is because the USA blow up Afghanistan after the September 11th bombings. USA dropped bombs on all of Afghanistan and ruined the whole country. There were no more houses, or jobs, or anything. Then the kids had nothing to do besides become a child soldier. Many of their friends and family died so it makes them very angry and want to have revenge on the USA. Some of them want to have support since their family is dead and they can get support from the armies if they become fighters.I am intrested in what does Usa army is doing wrong.