Huawei 5G kit must be removed from UK by 2027

If the protocols used for mobile networks were designed to be secure, most of the infrastructure couldn't do anything worse than a DoS attack. It'd still need some trusted servers for key management, but those could be standard hardware with relatively simple software.

How would that be in the interest of any government? Even in the most liberal democracies (I know of) there is a strong surveillance tendency.

That could be solved one layer up by just using Signal or similar for messaging and calls. Unfortunately voice over an LTE IP link is still quite unreliable compared to an actual call.

If China can cause a denial of service attack on a country by remotely bricking all the network infrastructure or even slowing it down to a degree, this would still be economically devastating at the least.

I think there's a difference worth noting between subtle monitoring & coersion vs. a full out act of war. By the time China is trying to denial of service the UK's 5G infrastructure we've got other things to worry about.

But they don't need to dos the whole country, just interfere up to the point of plausible deniability. They could do targeted outages for some UK firm at a stratetic moment or something.

Also in the case of an actual war, it's surely better to not have your entire nations communications under enemy control.

Very hypothetical, but it reminds me of Japan at Pearl Harbor adapted to 21st century.