"National security" has been increasingly been used over the last 5 years as a justification for measures that are actually much more broadly geopolitical in nature. A private individual using a Huawei phone or router isn't a national security threat to the US. However, in a broader sense, the US government sees the technological development of China as a threat to American strategic dominance, and has been taking ev…
The relationship is far from "purely hostile". We're giant trading partners. The relationship is mutually beneficial.
As was said here, our restrictions on Chinese companies are nothing compared to their restrictions on ours. And they've built their economy using so much stolen IP that's it's hard to believe this wasn't CCP policy coming from the top. [1] [2]
It's also not hard to imagine CCP hackers using homegrown telecommunications equipment as part of this IP "procurement" process. Personally I think a move like this is long overdue. As has been said here, what's wrong with deciding who your friends are and aren't? We're trading partners, that doesn't necessarily make us allies. Yes this is geopolitical, and if geopolitical issues aren't issues of national security, I don't know what is.
[1] https://www.cnbc.com/2019/02/28/1-in-5-companies-say-china-s... [2] https://en.wikipedia.org/wiki/Allegations_of_intellectual_pr...