The majority of American Jews are not Zionists, unless you consider all people who support the idea of an Israeli state Zionists, which would probably make a majority of all Americans "Zionists". American Jews like the idea of Israel in the same way that Irish-Americans like the idea of a united Ireland and Dominican-, Puerto Rican- and Cuban-Americans hate Castro. They know nothing of the real politics and are perfectly happy to be ignorant. It's just a nice idea to them and they'll send a couple bucks to somebody who espouses the cause.
Israel is a convenient military ally because her unpopularity in the region binds her to the United States. That's what the U.S. administration (including Nixon, proven anti-semite) has always liked about Israel.