(Am British expat, btw fwiw)
We had Boris Johnson and Liz Truss; the fact they happened at all demonstrates our system still has vulnerabilities.
I’m no fan of venerating a written constitution either, but I have an anxiety about parliamentary-sovereignty: events like Brexit and BoJo demonstrate a need for something to bind parliament, lest we get a 21st century Oswald Mosley. Right now we have… decorum and monarchy: a firewall made of damp serviettes.
Prior to Brexit, I feel there was some (if vague) kind of accountability from parliament to the EU - which is why/how Brexit revealed the fault-line in the Tories that split the proto-fash types from the amoral-business types to give us Reform/Restore today, and they’re uncomfortably popular. So what I’m saying is that Brexit weakened our accountability mechanisms more than people realize as the national-conversation focused only on economic impact and immigration.
In summary: do not convince yourself that “it cannot happen here”; nor that current safeguards (if any) are sufficient.
Oh I am not convincing myself at all. Like I say, every government ultimately ends up risking it and getting yanked back by the Commons (or the Lords in the case of e.g. 42 day detention of terror suspects, various other bad overconfident schemes like ID cards).
It's a pattern, a cycle. It is always under a sort of measured level of threat. But it is largely stable because at any time the party in power always has an iconoclast (Heseltine, Cook, Davies etc.) who is willing to get in the way, and there is essentially a Commons (or Lords) tradition of making sure that person gets heard.
And because the Prime Minister isn't really that special — just the loudest voice in his party, subject to its back-stabbing — there is a pattern to their failure, too.
(There is a bit of a concern that we're getting too used to them not lasting more than a couple of years, but I do get rather frustrated at the both-sidesing that is including Starmer with a run of utter inadequates from the other side)
Again the point I was making was only that the USA is getting a little further down the line towards wrapping up the clarity of the written Constitution with a layer of yes-but convention... It gets a lot more difficult from here.
There is a narrow window to pull it back, but as much as I think they are for the rule of law, I don't think the Democrats, even with potential rule-of-law-asshole injections like George Conway, are truly prepared to hew that close to the Constitution themselves.