I strongly disagree with that. I think of Americans would be willing to pay a little more for fruits and vegetables in exchange for knowing that their status as Americans means something special. A lot of us are proud to be Americans and believe that we have something worth preserving here.
I don't know many Americans who want to exchange the integrity of this country's legal system, culture and sovereignty for cheaper vegetables.
We have been doing it for years though. I do know what you are saying but in order to come to grips with this problem I think the solution needs to be pragmatic. Going forward I would not support anything that didn't include stict enforcement of the law.