U.S. is the prime reason why the Saudi monarchy has survived

"The BND lists the areas in which Saudi Arabia is adopting a more aggressive and warlike policy. In Syria, in early 2015, it supported the creation of The Army of Conquest, primarily made up of the al-Qaeda affiliate the al-Nusra Front and the ideologically similar Ahrar al-Sham, which won a series of victories against the Syrian Army in Idlib province. In Yemen, it began an air war directed against the Houthi movement and the Yemeni army, which shows no sign of ending. Among those who gain are al-Qaeda in the Arabian peninsula, which the US has been fruitlessly trying to weaken for years by drone strikes." "Again this looks naive: close alliance with the US is the prime reason why the Saudi monarchy has survived nationalist and socialist challengers since the 1930s."