Would a Confederal British Empire (inc America) be able to retain the Persian Gulf?

I know this is entering the realms of extreme speculation, with a time period far after a POD, but it's something I wanted to discuss. In our timeline, the British Empire controlled much of the Persian Gulf in the early 20th Century: a sphere of influence over southern Iran, protectorates in Kuwait, Qatar, the Trucial States and Bahrain, and an alliance with the House of Saud. Their decolonisation, partially caused by pressure from the US, saw them withdraw from the Gulf. The US stepped in to the vacuum, but due to changing times and their own anticolonial history, went for informal empire rather than empire: very close relationships with various Gulf monarchies, including propping them up with arms selling and places their own military bases everywhere.

But what if Anglo-America and the UK were always part of the same polity? What if some sort of confederal system was gradually set up between 1770s and 1830s, which had local autonomy in domestic affairs, but one co-ordinated foreign policy to dominate the world? I imagine such an entity would seek controlling the vast Middle Eastern oil reserves as a priority. Would they be able to hang on to it to the present day, with their combined and continuous military power?
 
Yes, I know there's a lot of butterflies, in terms of alliances and politics etc. But what I'm asking about is just the feasibility of a polity which had the combined power of the USA and British Empire behind it holding on to imperial domains.

In our timeline, every European colonial power had to give up their colonies, even those that tried to dig in, like the French in Algeria and the Portuguese in Angola and Mozambique. I'm wondering if a colonial power with six or seven times the population base and economic might behind it might be able to keep the local population from rising up. Or would the nature of new light weapons and political consciousness (assuming they are similar to our timeline) in that period meaning colonialism's game is up, regardless of the might of the metropole?
 
Yes, I know there's a lot of butterflies, in terms of alliances and politics etc. But what I'm asking about is just the feasibility of a polity which had the combined power of the USA and British Empire behind it holding on to imperial domains.

In our timeline, every European colonial power had to give up their colonies, even those that tried to dig in, like the French in Algeria and the Portuguese in Angola and Mozambique. I'm wondering if a colonial power with six or seven times the population base and economic might behind it might be able to keep the local population from rising up. Or would the nature of new light weapons and political consciousness (assuming they are similar to our timeline) in that period meaning colonialism's game is up, regardless of the might of the metropole?

Well, the Soviet Union managed to keep a large chunk of Europe under its thumb, so assuming the US-UK (KUS, Kingdom of United States?) is willing to put the required manpower into fighting any rebels, I'd expect that it could keep control of the Persian Gulf.
 
Well, the Soviet Union managed to keep a large chunk of Europe under its thumb, so assuming the US-UK (KUS, Kingdom of United States?) is willing to put the required manpower into fighting any rebels, I'd expect that it could keep control of the Persian Gulf.

That's true, although it does have the blessing of being contiguous territory. On the other hand, it was a poorer economic system than our US-UK would have. I am guessing that the territory would more than pay for itself due to the oil there. What sort of borders could be defensible from Arab tribal raids? You'd want to keep as many of these fields as could:

https://energeopolitics.files.wordpress.com/2010/04/middle-east-oil-and-gas-fields.jpg
 
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