The only country the Americans love and worship more than their own country is Israel. I can understand brain dead nationalism for your own country, but brain dead nationalism for another country, especially one doing the things Israel is doing... it's very strange.

There's at least a few factors in play...

Christian sects that believe the second coming of Jesus is not too far away believe that Israel's existence is critical to bring that to pass.

People with anti-muslim or anti-arabian feelings see Israel as a counterweight to muslim and arabian power in the middle east.

There's a lot of people who, consciously or not, equate anything other than total support for Israel with antisemitism.