That's just islander mentality. You can go to a tiny island in the north of Germany and they will probably tell you how they "do things differently around here" and how they're "a special kind of people". Or go talk to submariners of any nation. Of course none would tell you that "we cry a lot because we're lonely" or "we are afraid of our own weakness so we prefer to be alone". It's perfectly normal to try and turn your quirks and faults into strengths because you're afraid to get eaten otherwise in this darwinistic world. The ratio of special islanders is just higher in Britain because they haven't had regular friendly contact with continentals for as long as the Netherlands.
The so-called "increase in nationalism" is just a panicking of the vanishing. It is likely not to increase any further, but to implode as it dies out and gets replaced.
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