Earlier quoted context omitted.
Cartels are a feature of free markets. I would argue that it's good for the state to take some sort of interest in regulating them, one of several ways that I'm not a free-market fundamentalist. But arguing that the formation of cartels makes a market non-free is backward. Cartels emerge through free association in trade. Regulating them might make for a more functional market, a more efficient market (or it might no…
A market isn't free if prices aren't set by supply and demand operating under the guarantees of free exchange given by states (ie., property rights, and the rest). A cartel sets prices, and is one of the many ways markets are unfree. There's a ton of confusion created by libertarian sorts who fail to distinguish between government regulation which sets prices, and regulation necessary for the operation of the market…
That's true, but cartels can't enforce this. New or external firms can compete with the cartel. If a cartel reduces production or raises prices then it incentivizes competitors to meet the market demand with lower prices. The only way the cartel can exclude new firms is by controlling the entirety of some resource or enforcing the cartel usually in the form of lobbying for regulations.