Excuse me, but where the HELL do you get the idea that libertarians are pacifists?? The libertarian position is non-aggression, not pacifism, and typically non-agression in the sense that they won't ever START a fight, but once one was started, they would do their damnedest to finish it in their favor.
Worth repeating...
Maybe its because the LPs position on the War on Terror and the War on Islam is the same as the hyperlefties.
Since this thread started with an essay by L. Neil Smith, it's worth pointing out that some of his novels depict varying visions of a libertarian society. In both "The Probability Broach", and "Pallas", the citizens are peaceful, respectful of each other's rights, and ARMED TO THE TEETH against anyone who doesn't treat them likewise.
There are several gun battles in The Probability Broach, all enthusiastically participated in by the libertarian citizens in response to unprovoked attempts by others to initiate force (kidnapping, etc.) against them.
And in Pallas, preserving the right to keep and bear arms in defense against tyranny is the entire point of the book.