Monopolies and government,

Whenever you hear the anti-Capitalists speak of monopolies and the problems they cause they are often speaking of private industry. But the only oppressive monopolies that have existed in the history of Capitalist countries are government monopolies. You can't compete against the government for one reason; it's illegal to do so. State lotteries are a good example; in my home state of Tennessee I can play the Tennessee Lottery but I can't start my own numbers racket lottery (in Tennessee) because I would be breaking the law. Isn't it interesting that big government liberals in America oppose monopolies, while the government is the most oppressive monopoly in America?