@Debra Law,
So, your argument isn't Democrats VS Republicans, it's more progressive VS conservative.
You need both.
Progressive and conservative (at least what it seems like to me) is kind of a female version and a male version of an idea. The progressive says "this sucks, we need to change, let's try this", while the conservative says "hold on, the new idea sucks, it should stay the same". The progressive will point out everything wrong with an old idea and demand it be changed, while the conservative will point out everything wrong with the new idea and demand it be stopped. While we will always have the necessity for change and evolution, we still can't do it without understanding and implementing past ideas. The mix of the two, that system of checks and balances, is what makes the better idea.
Take pants for example. People have changed pants in about a million different ways, from zippers to buttons to floods to denim. They have been changed over and over because of fashion, function, etc. But, they are still pants. For hundreds of years, they have always been pants. Pants were as good of an idea as the evolution of pants.
The same idea as the pants is incorporated into politics and ideas.