I think it's because everyone wants to take the foundational concept and put their own "spin", their own little memorial, on top of it. Unfortunately that memorial becomes a tombstone.
That tombstone may involve "borders", or "anti-big business" (usually, actually anti-free-market and pro government regulation), or anti-sexuality, or anti-politically-incorrect drugs, or whatever else the people are willing to make an exception to permit State coercion for.
It's why we have factions of "left libertarians" and "right libertarians" instead of just a bigger group of libertarians.
Screw that!
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