[stealthcat]

You have to differentiate the Sunni and the Wahhabi/Salafi (which Wahhabis may call themselves Sunni.).

To know who are exactly are they: You may need reopen the history books for 19th century history about Muhammad bin Abd Wahhab, how his father and brother opposed him, what Ottoman's Muhammad Ali Pasha tried to do, etc. connection of the said events with Arab Revolt, T.E. Lawrence, the Saud family, Palestine, Fall of Caliphate 1924, ...Things pretty much went out of hand in Muslim world

From theological perspective (aqeedah) and approach in studying the religion, you can see how much Sunni and Salafi differs.

Probably the only reason Sunni today have diplomatic relations with Saudi Arabia because they control Makkah and Madinah.