No market is free when a monopolist controls it. For a market to be free, there must be actual competition. If the goal is to keep the market free, then the r

No market is free when a monopolist controls it. For a market to be free, there must be actual competition. If the goal is to keep the market free, then the role of the government is to intervene to ensure a state of competition when such state does not exist. If the goal is not to have a free market, then the role of government is to intervene and regulate the monopoly/oligopoly to ensure that people's constitutional rights are preserved and the monopoly is not used to obtain additional power or additional monopolies. AT&T was such a monopoly for many decades. They were prohibited from entering other businesses as it would just result in them expanding their monopoly.