Yes, but also airlines will completely fail without government support. The only aspect of aviation that is private is the buying a ticket and purchasing and operating planes, creating a thin fiction of a free market. Everything else is supported. The airports, the airline manufacturers (that also make expensive weapon systems via govt. contracts), the fuel system (supported by endless diplomacy, monetary policy, and war), radar and satellite networks, subsidies when revenue can't support operations.... it goes on and on.

The airlines are critical to a big country like the US when our passenger rail networks are so slow, so the government supports it. They should also support bus networks etc. I suspect much of their road policy is designed to support Americans buying cars, the second biggest purchase next to a house that most people buy. It's very cynical.