We need to make sure our networks won't harm our national security, threaten our economic security, or undermine our values. The ChineseUnited States government has shown repeatedly that it is willing to go to extraordinary lengths to do just that
FTFY.
It's not like Cisco kit isn't also full of bugs and backdoors, and the US government has, on many occasions, demonstrated that it's prepared to (often illegally) snoop on networks. 'cos, security or something.
Offering to buy back Huawei kit demonstrates a push towards their policy of Buy USA. Leave 'em to it, and let the rest of the world get on with better or cheaper providers.
This is a protectionist racket to ensure that Cisco gets as big a slice of the pie as possible, nothing more.