Why do they consider that belief controversial? Because they consider themselves entitled and qualified to run your life for you, whether you like it or not. And, of course, to bill you for the costs of their supervision.

Because I'm both a Libertarian and a loudmouth, I'm frequently hit with questions about libertarianism (and the Libertarian Party). Recently this one came up:

"What is the most controversial belief of Libertarians?"

Could it be our support of immigration freedom (and, generally, freedom to travel)?

Or our demand for separation of school and state?

Perhaps our hard-line support for gun rights?

Or our stand for legalization of all drugs?

How about our advocacy for keeping the government out of the sex lives of consenting adults (including marriage, and including sex for pay)?

Or our belief that who you do or don't do business with -- including for healthcare and retirement -- is your decision and no one else's to make?

My answer: It's all of those, and others. But it really boils down to one issue.

The most controversial belief of libertarians (and partisan Libertarians) is the belief that you're generally both more entitled and more qualified to run your life than someone else is.

Who considers that belief controversial? "Mainstream" politicians and their supporters.

Why do they consider that belief controversial? Because they consider themselves entitled and qualified to run your life for you, whether you like it or not. And, of course, to bill you for the costs of their supervision.

Politics isn't persuasion. Politics is force.

Whether the issue is immigration, or education, or self-defense, or drug use,  or sex, or commerce, or, heck, what color you paint your house or how long you let the grass on your lawn grow, the political approach is not to present an argument and trust you to make the right decision. It's to decide "for" you, then beat you down if you disobey (or fail to pay them for their services).

Libertarianism -- even the "political" variety -- isn't really very political at all. It's anti-political. As one fun meme puts it, libertarians are "diligently plotting to take over the world and leave you alone."

Libertarians only recognize one valid constraint on your actions: A universal, mutual constraint against aggression, also known as initiation of force.

The simple version, courtesy of Matt Kibbe: Don't hurt people, and don't take their stuff.

When you throw the first punch, or pick someone's pocket, or otherwise forcibly interpose yourself between someone else and that someone's life, liberty, or property, you're not running your own life. You're trying to run theirs.

And that's the only thing libertarians agree you should be stopped from doing or penalized (in a manner consistent with restitution, not "punishment") for doing. Even if it's "for their own good."

If you're down with that idea, congratulations: You're a libertarian.

If you're not down with that idea, I hope you'll think it through more carefully.

Thomas L. Knapp (Twitter: @thomaslknapp) is director and senior news analyst at the William Lloyd Garrison Center for Libertarian Advocacy Journalism (thegarrisoncenter.org). He lives and works in north central Florida.