There does seem to be a natural tendency for people who care about tradition (and those who want to preserve it) and those who don't care about tradition (and those who want to change it), which lends itself well to the idea of conservative vs progressive. However, saying conservatives in the US should be the same as those in Iran would be ridiculous, since they are not using the same starting point with regards to conservation. Calling something conservative should be in relation to the thing that you are trying to conserve. The value of conservation vs progression relates directly to the morality or rightness of that which is being preserved or changed.

Naturally, our founding fathers weren't conservative. They were progressive. That doesn't mean that modern day progressives are the same as the founding fathers. The founders used philosophy and reason and build a government based on the principles JJ was describing above. There was variation in their ideology from the onset, especially in the scope of government, such as the differences between Hamilton and Jefferson, but they all hailed the constitution as the defining document of the federal government.

I don't think the modern conservative party could exist until the threat of a new type of government could rival the constitutional Republic. In this case, I think you need to look back to the 50's when the threat of socialism and communism were on the rise. Buckley, Friedman, Kirk, just to name a few, were the forerunners of modern conservatism. This is when preservation became a staple of the political movement. Within the conservative party, you will still see Hamiltonians and Jeffersonians, but you won't see Marxists.

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