Why do Americans love to talk about how the "free market" makes everything better when every other developed country has proven this to be historically untrue?

To me it's just so bizarre. It's like Americans have some deep rooted delusion that their economy is better off when companies are allowed to regulate themselves when that has never been the case in the history of capitalism. I work a regular office job so I'm not some anti-capitalist commie, but I truly do not understand the belief of "the free market can solve anything."