The consequences of installing spyware on your devices and trying to spy on the US.
Not to mention there is no public evidence of Huawei doing this -- but we have mountains of evidence of the NSA doing it! Hell, the NSA actually hacked into Huawei's internal infrastructure before[1].
[1]: https://techcrunch.com/2014/03/23/latest-snowden-allegations...
Both are bad, right?