What on earth does sitting do to show your lack of support? Even if you don't agree with parts of your countries policies, you need to support it as a whole, for what it is: CHANGING. Countries, laws, etc are always morphing into what the public wants (or thinks they want). The Pledge doesn't say "I like this country the way it is, and don't ever want anything different." It says that you support your country.

EVERY one should be able to stomach that.