Who Holds the Monopoly on Reason?

There are essentially three distinct competing ideologies in the United States these days.  There are the Leftists, the Conservatives, and the libertarians.  All three have a their own distinct beliefs and while there are some overlapping, they are for the most part the three different movements.  Not all three are equal in size and influence on the average voter, but all like to believe that they hold some monopoly on reason.
For liberals, or Leftists, they tend to believe that they are the only side that makes sense and usually most independent observers will say that these people are largely crazy.  But that wasn’t always true.  Back during the turn of the century, Leftists in America were mostly intellectual-types, but largely had more grounding in practical matters.  Karl Marx even understood the fundamental laws of economics and formulated his own brand of Leftism based on those conceptions.
Ultimately, as the Left became more and more influential, they became less and less reasonable.  Many radical Leftists, like the remnants of the rich white people who called themselves “Weathermen”, turned out to be nothing more than homicidal maniacs.  I guess that’s what I have to do in order to win a professorship without having a real degree.  In any event, it’s quite clear to me that the left has never been reasonable, at least since when the Soviets took power.
The conservatives often portray themselves as reasonable or holding some higher rational ground when it comes to debating.  But I have yet to meet a conservative who didn’t vote Republican in spite of the evidence that Republicans generally don’t care about conservative ideas.  I think they tend to suffer from some kind of battered wife syndrome because they are always duped into voting for a RINO believing that the lesser of two evils is better than the greater.  I’m pretty sure that God said all sin means death though, so they have a screwed viewpoint on evil.
Libertarians tend to believe themselves to hold the monopoly on reason these days as well.  Heck, one of the most popular online magazines libertarians have is called Reason.  But I don’t believe them to have any more sense than the rest.  For one thing, many libertarians tend to take the liberals' logic when it comes to anti-war policies, which is usually irrational, and some even have a serious anti-military bent.  I tend to view the military with a certain level of neutrality.  To me, they are more like having a condom in your wallet (if you are non-religious) in I don’t want to use them if I don’t have to.  Libertarians also tend to view human beings as rational beings, which is a foolish stance to take in my view.
I believe that none of these ideologies has any more hold on reason than anyone else.  All sides exhibit levels of irrational logic, although some much more than others, and so I don’t delude myself into believe that because this person is a libertarian, he must be making sense or that this person is a liberal and makes no sense.  When it comes down to it, reason is nothing more than a tool to fit your own beliefs.  While it can prove the legitimacy of your arguments, that does not mean that the other side isn’t able to do so as well.
I recommend that anyone reading or listening to anyone with a political message make sure it fits with your own beliefs and if it doesn’t, analyze why.  This does not mean you should stop reading or listening to them, but that you have a responsibility to yourself to understand what they are saying and be ready to not swallow their supposed logic whole.