Well, as the royal family of Jordan hails from the Hejaz, this was very much a likely scenario before the British and French decided to cheat the Arabs of what they were promised. The Hejaz was, and is, a much more liberal region than other areas on the peninsula, and this would've kept Mecca and Medina out of the hands of the reactionary fascists in Saudi-Arabia and that way never given the Saudis the power they have over the Islamic world today. If this state could've lived on I'm sure it would've meant a more stable Middle East.