Good, let them slaughter the Saudis. Then when the rubble settles, give the land back to the King of Jordan whose family originally had the Hejaz before they stole it from them.
You can at least be reasonable with the Hashemites, and that says a lot.
Just checking you know the Heshemites are part of the Arab Quarish tribe; Mohammad ('the islamic prophet') was a descendant of the same Heshemite tribe (I think his great grand-father), of one clan belonging to that tribe, and so was Mo's daughter Fatimah.