Communism is a form of government. Without government in the equation you end up with plain old voluntarism - and nobody has a problem with a group of people who just want to share everything with each other. The problem comes when that kind of system is placed on a national level and the government forces people to participate in the system with the threat of violence. Communism/socialism has been tried before early on in America - the result was that since everyone got the same rewards for varying amounts of work nobody did any work since they would get paid anyway - and similar results are found in any system where socialism or communism is introduced which is why some people in a socialist society must be forced to participate in order to provide the goods and services required by the society.