The email was not meant to be public. Writing to a small-business owner on Staten Island, a researcher for the Senate Small Business Committee said Republican staff had been probing “Amazon negligence related to Chinese influence and have found compelling evidence.” The note named no evidence at all.

That is more or less the whole of what the committee has said, and it is a lot to leave unsaid. Amazon.com is now under investigation for allegedly letting China sway its online store, according to Bloomberg, which spoke to two people interviewed as part of the inquiry. The company declined to comment. So did the committee.

The more telling part is where the probe came from. It did not start with grand national-security theory. It started with a scam.

From a bribery market to a China probe

In June, Bloomberg described a shadow market in favours: Amazon employees based in China selling help to the merchants who sell on the platform. Jack Nekhala, a Staten Island inventor whose product keeps sheets on mattresses, had recorded an intermediary offering exactly that. Her Amazon contacts in China could do him favours, she said, for a fee.