Well I hope your right. That is the million dollar question. Can you think of an example of a *treaty* being found unconstitutional? I can not. Can you think of an example of a *treaty* being treated like a law and challenged in court? I can not. Therefore, until I see these things happen, I will remain worried that the treaty mechanism is main one they will use to subvert the Constitution.
Just out of curiosity that's how I read Sandra Day O'Conners comments. How do you read them?
She said: Well, you always have the power of entering into treaties with other nations which also become part of the law of the land, but I can't see the day when we won't have a constitution in our nation."
I see that as her saying that even though we'll be seeing more treaties being signed in the future (which I don't necesarily agree with), those treaties will still need to pass the test of Constitutionality. Remember, treaties need to be ratified by the Senate (by a 2/3 vote, if I'm not mistaken), so they can't really be imposed on the American people unless the Senate is somehow full of internationalists.
You don't hear of treaties being brought up in court because most currently existing treaties are very weak in their ability to override American law. Very rarely, a State law will be overturned on treaty grounds- that last one I remember is a California environmental law that clashed with a treaty the US had entered into. That's really no different than a state law being overturned because it clashes with any other Federal law.
I can't really think of any currently existing treaty that I would consider unconstitutional. Few treaties are self-executing- rather, they rely on the signing countries to pass laws that will make the provisions of the treaty enforceable in those ocuntries. So, if the Senate somehow ratified a treaty that, say, banned all firearms, and then Congress enacted legislation to empower that treaty, the laws would still have to survive Constituional scrutiny. There's a lot of checks in the system, so I'm not all that concerned that treaties will be able to take away Americans' rights.