I don't want this to happen. I have no idea if it will happen.
The key moment is if British police (they do have armed units) or military faced a large unarmed mob of angry native Brits - and they start shooting. Everything explodes at that point, it all changes. Hopefully not.

Another possibility is that the British police or army refuse to shoot their countrymen - and there are plenty of historical precedents for that.
The point is that it can be acutely dangerous for a regime to start shooting at its own population. And, that's the point of guns,
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is to shoot with them.
If either the UK or the US begins shooting at significant portions of their native populations - they've already lost. Their economies, world power, domestic peace, it's all down the drain.
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