Reasons for the Untied States' loss in the Revolutionary War?

I have seriously lost faith in the American education system. I feel compelled to correct you before I go and hang myself after reading this question. The President is the leader of a free and Democratic United States. The United States Congress holds the ability to draft and write laws, pending approval from the President (or in some cases even overriding him.) The Supreme Court decides if laws are Constitutional. The Executive branch is responsible for carrying out Congress's laws. The Declaration of Independence officially separated the United States from Great Britain and the Constitution sets the framework for the government. If your teacher honestly believes that the United States is still under British rule, he needs to be fired.