If you mean that literally, then I have to ask who does the shutting out and how? Closer to the truth is that American Jews are a very effective voting block and have been for a long time. Ironically, their primary motivation is the presence of sentiment like yours.
Sweeping statements and all-or-nothing conclusions are fair enough on this political forum, I suppose. But it's also fair, I think, to call them what they are and that's part of the problem, not the solution.
I happen to also feel that Israel gets too much of a pass with us here in the US, and there are plenty of others who would agree. But that discussion is being repressed.
Each side embellishes, but like it or not Israel has credibility that its opponents don't enjoy, despite stories like the one referred to by the OP. If this country's opinion matters to them, then Israel's opponents and their sympathizers need to improve their credibility.