American conservatives are interested in conserving the institutions of American government. Totalitarianism and communism aren't consistent with American conservatism in any sense as conservatives believe that the Constitution and Bill Of Rights are worth preserving (and not just because they're Traditional American Artifacts, but because we believe in what's in them).
I'm a conservative because, in part, I want to preserve the traditions of American government and I believe that American social stability is worth conserving. I believe that applying the force-or-fraud test to the entire body of American law would weaken social stability, hence, libertarianism isn't the political philosophy for me.
In a communist or totalitarian state I wouldn't be considered a conservative; I'd be considered a reactionary.
Conservatives in America have also traditionally stood for smaller government, lower taxes, less federal spending and fiscal accountability. Sadly, conservative politicians seem to be getting away from that message, but it must be remembered that they're dealing with a Democrat-controlled Senate and they don't control the committees anymore.
Even if they are unconstitutional.