United Airlines stock continued to plummet yesterday after a passenger was violently removed from his seat after refusing to give it up.

The whole incident was caught on camera - complete with screaming passengers and bloody noses - and it's rapidly turned into a public relations disaster for an already struggling airline.

But the startling images out of Chicago's O'Hare airport are an example of more than just of how not to handle bad press.

They're also a very instructive - if very violent - example of what happens when you double down on de-regulation.

I see a bright line from Carter and Reagan deregulating the airlines to what happened United Airlines Flight 3411 and the PR disaster that's followed.