And if Saudi Arabia would become socialist in the 1960s?
The points of divergence could be many, but I believe the most likely an extension of the Yemeni revolution that founded the Democratic Republic of Yemen (1967-1990) and made the South Yemen the only Arab country to become a full member of the Socialist Block led by the USSR.
For the revolution produced some progress and there was a serious risk to expand to the entire Arabian peninsula, but it was contained in OTL.
And if the Yemenite example should be extended to other states of the Arabian Peninsula, including the rich Saudi Arabia?