There are many people who mask hatred for Jews behind anti-Israel rhetoric.
Some say this is criticism over Israeli policies, but when you dig a little deeper they resent Jews generally and especially the idea of a Jewish state and/or Jews with power.
But there is nothing wrong with being critical of Israel's behavior, any more than any other nation and its policies.
There is a great deal of Jew hating and Jew baiting going on the US. Groups like the Aryan Nations and other neo Nazis, so-called "Christian Identity" groups, racist skinheads and the KKK etc. spout this kind of stuff constantly.
Likewise, anti-Semites often come up with various conspiracy theories linking Jews to almost anything negative and despise Jewish defense organization such as the Anti Defamation League or American Jewish Committee that expose this nonsense.