WASHINGTON — President Donald Trump won’t let up on Amazon. He’s been assailing the online retailer for days, zeroing in on a “scam” contract with the U.S. Postal Service that’s actually been judged profitable for the post office.

TRUMP: “Only fools, or worse, are saying that our money losing Post Office makes money with Amazon. THEY LOSE A FORTUNE, and this will be changed. Also, our fully tax paying retailers are closing stores all over the country…not a level playing field!” — tweet Monday.

TRUMP: “If the P.O. ‘increased its parcel rates, Amazon’s shipping costs would rise by $2.6 Billion.’ This Post Office scam must stop. Amazon must pay real costs (and taxes) now!” — tweet Saturday.

THE FACTS: Trump is misrepresenting the contract that has the post office deliver some Amazon orders. Federal regulators have found that contract to be profitable for the Postal Service.

As well, people who buy products sold by Amazon pay sales tax in all states that have a sales tax. Not all third-party vendors using Amazon collect it, however.

As for the post office, package delivery has been a bright spot for a service that’s lost money for 11 straight years. The losses are mostly due to pension and health care costs — not the business deal for the Postal Service to deliver packages for Amazon.