James Petras, the man who first denounced Obama as "the First Jewish President" (meaning he's totally sold to the Zionists) has another article online on this crucial issue affecting global politics and very specially regional politics of the Middle East and domestic politics in the USA.
James Petras, Bended Knees: Zionist Power in American Politics.
(Shouldn't be "bent knees"? Some native English-speaker please clarify this to me).
Petras mentions that maybe more than 50% US Jews are not active Zionists, many being even harshly critical of Israel and the Lobby. However the remainder are fanatic militants of a well organized network that has extended control over US economy and media, and is highly structured, both sectorially and geographically (and not just in the USA, of course) with their goal being not their country's but those of a foreign power: Israel.
Too long to excerpt here but a must read.