How did American Jews get so rich?

Since the mass immigration some 100 years ago, Jews have become richest religious group in American society. They make up only 2% of US population, but 25% of 400 wealthiest Americans. How did it happen, and how crucial is their aid to Israel?
by Tani Goldstein
World Jewish Congress President Ronald Lauder sparked a row recently by calling on Israel to launch immediate peace negotiations with the Palestinians. The statement was perceived as criticism against Lauder's personal friend, Prime Minister Benjamin Netanyahu.