Skillfully diplomatic? He's overtly mocking the behaviors of the British Empire. You're also off on your timeline. The 'shot heard round the world' would happen in 1775, not 1773, years after this letter was written. Even the Boston Tea Party hadn't yet happened. His overall complaint, and its solution are also rather plain. Britain was trying to impose their authority like a foreign occupation, rather than treating the colonies as an equal and integrated part of the Empire.

There's probably no timeline where Britain holds onto the colonies simply because of the distance involved - people don't like being ruled by those who don't represent themselves in any meaningful way. But they almost certainly accelerated the end through hubris. They were the Mighty and Civilized British Empire, and the colonies were just uncultured backwoods vagrants who's existence was only at the leisure of the Crown.

> Britain was trying to impose their authority like a foreign occupation, rather than treating the colonies as an equal and integrated part of the Empire.

...to be fair, Brits back at home paid way, way more tax than Colonials did, and also had to pay market rate for tea, among other things. If Britain treated the Colonies like the rest of Britain, it wouldn't have taken until 1775 for them to revolt.

Didn't have to be that way, though. Treat the Colonies more like the Persian Empire treated its conquered states, and the USA today would just be "lower Canada".