Just a simple question but what ultimately lead to the withdrawal of British support from HUSSEIN bin Ali in 1923? Was it his claim to the capilharate ? I seem to recall that the Saudi held off invading Hejaz until this support was removed...
I think there was a fair bit to do with the fact that he was still pushing to have a unified Kingdom under his rule covering all the bits 'liberated' from the Ottomans. Plus a Saudi-Hashemite conflict was inevitable and the Saudis had recently proven to be more dependable/stronger allies having just crushed the Rashidi Sultante of Jebbel Shamar.
It was probably also because the Hedjazis had been playing off the Germans and British. Although they sided with the British in the end, they had taken money from the Germans to publicise a jihad against the entente, but it never really happened.
I think it was more complicated than that. The British commitment to the Hashemites was almost always haphazard because the leadership in India preferred Ibn Saud for their own reasons.