Science boycotts over envirnomental issues?

Here's an issue below the public opinion horizon, but one that could become crucial in future years. Is it wise to boycott a nation's academic and scientists over that country's action or laws? There's been some move in China to boycott over their population control law. Other science organizations have suggested boycotting Israel for political purposes.

It is easy to imagine countries trying to cut emissions pushing boycotts of U.S. or Chinese scientists if those two leading air polluters don't take action on global warming.