Taxation with Representation

What if from the very start, English colonies in America are incorporated into England and send MPs to parliament?

the key part of this is 'from the very start' and it would take a bit more than representation. The Brits would also have to keep a close eye on proper tax and customs collections, and crack down on smuggling. One of the big things that kicked off the ARW was not just 'taxation w/o representation', but the fact that the Brits had really not paid attention to collecting even the lesser taxes that were applicable to the colonies, and turned a blind eye to smuggling, and then suddenly decided to crack down on it, all at once...
 
If i was in england's position in your timeline and am being slowly marginalized, I would:

Decolonize
Or come up with away to keep the center of power.

The only way I can think of is actually go for written constitution that formalizes the relationships of the dominions and kingdoms under the empire. Put in a few perks just for the old kingdom, and hope for the best.

London is the capital forever, or it might eventually get moved to New York.
I'm sure there are other little things that could be sneaked in, that could continue to make the british isles a center for power into the 21st century.

The American colonies would still need to come to London to raise money for investments. London's status and the empire's financial capital would give Britain significant leverage.
 
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