Conservatism, in its most basic form, is a perfectly respectable philosophy. Its purpose is not to put the brakes on "progress", but to exercise caution about whether a proposed cause constitutes "progress" in the first place. It prevents headalong rushes into changes that have not been properly thought through.

Science itself is conservative as a matter of principle. New ideas do not get simply waved through on the basis that they are interesting or sound good. They have to prove themselves better than the existing ones first, with the ability to address that which we can already explain as well as that which we cannot. (Edit: also what zengardener said ^^{^} while I was typing this.)

What passes for "conservatism" in US politics is something very different. Shovelling no-bid contracts to your friends is not conservatism. Starting foreign adventures and running up massive debts to pay for them is not conservatism. The Spectator backed Obama in 2008 because it reckoned he would be a better conservative than McCain - it is arguable whether this has proven true, but the case was certainly based on rational grounds. To be a standard-bearer for US conservatism, you apparently now have to show support for an entire smorgasbord of stuff, from the socially questionable to the downright crazy.

It is hard to see why this should be so. It is almost as if "conservatism" is now like your PC, pre-loaded with a bunch of crap that you don't need, don't want and can't uninstall. Thinking that it might be a good idea to keep government small now puts you in the same camp as the lunatics who want to do vaginal ultrasounds as a pre-condition of getting an abortion or rant about science being evil.

Still, it is as nonsensical to assume that all "conservatives" are the same as it would be to assume that everyone in the other camp is a Stalinist.