I think Ron Paul confusion answers it best. He just climbed up on the wrong platform and podium to voice his thoughts. From here on the list of my answer would be too long. : - )
What podium would that be? Are you trying to say that you think he shouldn’t be a Republican because he doesn’t agree with GWB on foreign policy? What other things must we all be in agreement with GWB on to be a true Republican? Immigration? Campaign finance reform? The farm bill? Are you trying to say that he shouldn’t be a Republican because he doesn’t trust the government investigation into 9/11 so far? When can we resume mistrusting the government? When someone with a “D” next to their name is president?
My idea of libertarian is someone who believes in:
small, unobtrusive, non-oppressive government
low taxes, possibly including no income tax
freedom
liberty
property rights
self-defense rights
not getting involved in Wilsonian, never-ending foreign entanglements (like George Washington warned against)
So which of those big ones is it that you have the biggest problem with?