As I wrote elsewhere, fishing turned out to be a surprising point of contention between France in the UK. Mostly for the symbolic value: 0.1% of the GDP in both countries, but fishermen are an important constituency and the French presidential elections campaign (April 2022) is gearing up. On the Brit side, picking up a fight with the French has always been a winning diversion strategy - the tabloids are too happy to oblige.

This could get really ugly:

Frank: Is there no low to which Boris Johnson's government cannot sink?

I'm afraid we haven't seen the bottom yet. One point though: the Tories feel they can bully a small country of 5 million people that they have occupied for centuries with impunity. Trying the same playbook with a country of similar size and GDP, which controls the continental half of the strait through which the vast majority of the UK trade passes and literally controls a significant chunk of the electricity delivered to the island, is another kettle of fish entirely (pun intended). Not to mention the EU as a whole.