How to stump a leftist conspiracy theorist

Dr. Marko Maunula is a professor of American history at Clayton State University in Georgia.  Originally from Finland, he writes in the Finnish weekly Suomen Kuvalehti about American life.  He recently wrote several interesting articles about antisemitism.

In one recent column Maunula writes that he spoke to a leftist student of his about the Syrian civil war.  It's a plot by the Rothschilds, the student said, in order to gain control of the Syrian Central Bank.  The Jews also control the media, which is why we don't know the truth about what's happening, and they also control Hollywood, which puts up a smokescreen to obscure the truth.

Maunula responded with a question: what do you want to do about it?  If you think Jewish success is a problem, what should be done?  Should Jews be banned from working in the finance, media and entertainment industries?

The student, of course, did not have an answer.

Manula says he's had such discussions before with both American and Finnish leftists.  They always come back to the same themes: the Jewish-Western-banker conspiracy.

This shows the two aspects of Leftist paranoia:
1. Antisemitism - the Jews are responsible for all evil.
2. Lack of any real solution - the system doesn't work, but nobody says what should replace it.

Maunula told his student: either you punish success and ban Jews from the fields where you think they over-excel, or you learn from it and try to excel as well.

What do you think they did?