It’s inevitable that a billionaire fixated on airing petty social grievances against his peers over Twitter would occasionally pick fights with the right enemies for the wrong reasons. Donald Trump’s recent call-outs of Amazon over what he claims is a one-sided contract with the United States Postal Service is just such an instance.

Trump has been taken to task in the media over his claim that USPS loses $1.50 on every Amazon package it delivers — a falsehood that likely originates in a Wall Street Journal op-ed written by a hedge fund manager with a heavy stake in FedEx. The president may or may not be aware that the Postal Regulatory Commission is charged with examining and confirming the profitability of the contract for USPS on an annual basis.

Rooted in poorly sourced talking points culled from the frothing enemies of all things public sector, Trump’s claims fit the well-worn conservative narrative of government largess rigged to exploit the taxpayer. Nevertheless, there’s a certain degree of truth to the insinuation that Amazon is getting the better end of its 2013 Negotiated Service Agreement with the Postal Service. In reality though, it’s not the federal balance sheet that’s hurting — it’s USPS’s thinly stretched, union workforce.