Open Source
Huawei should point two fingers at the govt of the USA by open sourcing its firmware and then ask the USA to point to the Chinese gov't bugs.
Huawei should document how to compile & install the firmware - then challenge Cisco, etc, to do the same.
Huawei makes its money by selling hardware so this should not be a huge problem. Yes: some of its competitors may find interesting things to copy; the NSA will produce its own firmware that creates a NSA back door; others might even improve/debug the firmware - making it better.
The USA gov't will then have to invent some other excuse for protectionism.
Are there Chinese gov't back-doors ? Quite possibly. But if the bugged Huawei gear is not being sold any bugs are pointless, so they might as well support clean firmware and get the economic benefit.
In fact all security sensitive software should be Open Source, let's start with mobile 'phones and desktop operating systems.