Thanks for the wondeful replies!
We need to register for a company in the US because we are trying to do a crowfuding campaign (think Indiegogo, Kickstarter, etc.), and most of our future customers will be based in the US.
We will run our Chinese operations (procurement/project management/logistics) from a separate Chinese/HK company so we are not trying to disuise per se anything per se.
So in theory the US company will only collect payment from crowdfunding platform and procure from the Chinese/HK company, and all of these will be conducted by officers (US and non-US citizens) outside of the US. Would these somehow create a tax nexus in any of the states..?