What is the theme in Sleeping with the Devil: How Washington Sold Our Soul for Saudi Crude by Robert Baer?

A second dominant theme of the book is the relationship between the House of Sa'ud and the Wahhabis. The Wahhabis are followers of their founder, Muhammad ibn 'Abd-al-Wahab, who lived in the eighteenth century. He believed that Muslims had strayed form the teachings of the Qur'an and preach a return to a pure form of Islam based on the Qur'an and the Sunna, the code of conduct. His followers are known as Wahhabis. They preach death to infidels. The Wahhabis are the basis for the fundamental Islam.