In America you swear your allegiance to a piece of fabric, and to support 'one nation under god' despite the fact that America is supposed to be secular...

Reality: These things are actually more based in culture and tradition than law.

Technically, it's to the thing for which the flag is a symbolic representation. One Nation, under God is arguably not an invocation of Christendom, but of deism, or the next biggest fish.

Spot on on the being based more on culture and tradition than law though.

> If we compare and contrast with America, nobody needed to swear allegiance to Trump at the border. They let in a bunch of people who would have actively and publicly wanted him gone. One of these two countries is pretending that birth literally should confer special privileges.

Trump is not equivalent to the Queen in role. The Queen is supposed to be a figured head only, a bit like the American flag. That's why this news is controversial because it's an abuse of position.

Real power in the UK rests solely in the House of Commons.

The last monarch that forgot that publicly had their head cut off in 1649.

That fact is celebrated every opening of Parliament when they slam the door in the face of the Queen's representative Black Rod, exactly so that she remembers.

You might not like the unwritten rules that govern the UK but they've worked pretty well so far and have been malleable enough to be reformed whenever there's been a problem.

The problem that comes into play with over-malleability is that you can end up weaseling your way into anything with enough time. Hard, explicit limits have their place, even if you do need to rein in the linguistic drift from time to time.