The Saudis use their vast oil wealth to finance the Wahhabist Islam that Saudi Arabia follows. Called a "virulent" strain of the religion, Wahhabism is intolerant of all other religions and calls for the rule of Islam throughout the world.
Today Freedom House, a non-partisan group dedicated to religious freedom, published its report on Saudi-financed mosques in the US's largest cities and the doctrines those mosques are spreading, as summed up by the Dallas Morning News' Rod Dreher on National Review Online:
Freedom House has found that mosques around the country are distributing Saudi-produced literature urging Muslims to hate Christians, Jews, Americans and even moderate Muslims. One document allegedly picked up in a Houston mosque directs Muslims to quietly prepare for jihad that will install an Islamic regime in the United States. You must read this report yourself, because I have very little confidence that the MSM will report its findings. Our government and our media have a see-no-evil policy when it comes to this kind of thing.