The antisemetic conspiracy that claims that the Jews are aspiring to take control of the world was concieved when the National Socialist (Nazi) party began amassing power in Germany. They also related the Jews with communism and the poor state of economy of Germany at that time. Because the Jewish didn't work in physic jobs such as farming or building, but rather banking and generally the market- it was the perfect thing to latch the antisemitism on. Truth is, it's just the fear and hatred towards the different (the Orthodox Jews wore their attires back then just like they do now) that drove people to despise them so much, not to mention their desparateness created by the terrible economy. The conspiracy theory about the Jews is just another leftover fabrication made in the days of Nazi Germany. I'm actually surprised there are remnants of this conspiracy at all after all this time.
Israel is by far not controlling the USA, but rather the other way around. Besides, the USA is just siding with Israel since it's the only ally and influence they can have in the middle east.
According to what both of us say, the conspiracy theory should be that the Americans are trying to take over the world, not the Jews. :P