I suspect the 1950's nationalism and the perceived identity crisis that you refer to isn't weird to those who are still alive or were born in the immediate aftermath of WW2, whether you were a come-over or not. I was born in the fifties, my brothers were born immediately after the war and I think it's fair to say that my parents and millions of others didn't have much other than the pride as a nation, a British nation, that they survived the war. The Isle of Man certainly paid the price in both world wars, you only have to look at the village and town memorials to realise that. Those lives lost and those that survived were not fighting only for IOM but for Britain, the whole, the bigger picture. It mattered. And to some it still does.
If anyone asks me what nationality I am I always say British not English, which technically I am being brought up and having lived in the East Midlands for the first 25 years of my life.
I certainly think that there's an element of faux British nationalism in UK politics.
And I think the Special Relationship (or lapdog as you prefer) with USA is as a direct result of both world wars as well.