On one side, there is a large group of entertainers boycotting Israel because of the occupation. On the opposide side, there are a few "B listers" who will go to Israel and make a "virtue of necessity". A gig is a gig. In the middle, there is by far the largest group who just want to keep away from controversy. The best way to do this is to say nothing and do nothing concerning Israel and for sure, not go to Israel. It is this silent majority that is influenced by Waters and other boycotters.
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from the article: Roger Waters voices support for Israel boycott