what would be the best POD for balkinzing the USA?
I'd have to agree that right after the revolution is the most likely time. If the Constitutional Convention fails to reach agreement, some states might see the articles of confederation as more trouble than help and just walk away.
Doesn't that make the individual states easy pickings for imperialists? The British Empire would have found retaking all 13 at once very difficult and expensive. But 1 at a time? Certainly more doable.
The easiest way is for the Constitutional Convention to Fall. What might be more interesting is seeing if we could perhaps get a balkanized US due to a decisive British victory in the War of 1812?