A while back I wrote of the “libertarian penumbra“:

Libertarians are famous for their internal disagreements, but they have
far more beliefs in common than their core position requires.  For
starters, even non-consequentialist libertarians generally believe that
libertarian policies have good consequences.  Almost all libertarians
think that free markets are better for economic growth, legalization of
drugs would not radically increase drug use, and rent control causes
shortages.

The more interesting fact, though, is that
libertarians have many beliefs in common that have little to do with
the consequences of liberty.

I remembered this post while reading David Gordon’s critique of Nick Gillespie and Matt Welch’s The Declaration of Independents.  It’s hard to be sure, but David seems to reject the very idea of a libertarian penumbra.  Gillespie and Welch identify tolerance as “the most important social value,” but David demurs:

This very much differs from the conception
of libertarianism defended over a lifetime by Murray Rothbard.
As Rothbard saw matters, libertarians are committed only to defining
the permissible use of force. They are free to adopt whatever
attitudes they wish towards people’s lifestyles, so long as they
respect rights. They are emphatically not required to be “social
liberals”.

“Required”?  Of course not.  But tolerance and libertarianism are highly correlated, and it’s no coincidence.  Why not?  Most obviously: If you deeply hate another noteworthy group, coercion is the only plausible way to rapidly and decisively eliminate it.  The deeper your hate, the more tempting coercion becomes. 

Sure, we can imagine a “libertarian Trotskyist” who spends his life trying to persuade the bourgeoisie to voluntarily commit suicide.  But it’s unlikely that such a person has ever lived, or ever will live.  If your end is the elimination of millions of people, the means of coercion will call to you like the One Ring to the Nazg├╗l.

The same point works at the opposite end of the continuum.  If you have a live-and-let-live attitude, coercion naturally holds little appeal for you.  Sure, we can imagine a “homicidal hippie” who reluctantly advocates the extinction of millions of people against whom he bears no ill will.  But once again, it’s unlikely that such a person has ever lived, or ever will live.  In the real world, tolerance and libertarianism walk hand in hand.