I don't buy this argument, sorry. Yes, we have a high standard of living compared to other countries. Does that mean we can't be upset that the Bush Administration is making things harder on us? Absolutely not! The American dream is about not being satisfied with what's good enough, but to try to make things better. Of course we should be thankful for what we have, but that doesn't mean we should sit contently and be happy when our leaders are taking us in the wrong direction.
As far as the troops -- that argument sounds exactly like the "if you don't support the war (or the administration), you don't support the troops" argument, which is completely wrong. Am I thankful that they "died for my freedom?" No, because they didn't need to. I'm angry that our troops are dying in a war that we should never have had to fight.