Most fundamentally, Trump’s attacks on Amazon are in line with his populist politics. In a Thursday tweet, Trump said Amazon was “putting many thousands of retailers out of business!”

I have stated my concerns with Amazon long before the Election. Unlike others, they pay little or no taxes to state & local governments, use our Postal System as their Delivery Boy (causing tremendous loss to the U.S.), and are putting many thousands of retailers out of business!

— Donald J. Trump (@realDonaldTrump) March 29, 2018

There’s plenty of evidence for this view, as retailers nationwide close stores and declare bankruptcy in droves. Retail jobs have declined in rural areas, where Trump’s support is strongest. But there has been some pushback against the idea that retail as a whole is in trouble, or that Amazon can be blamed — the stores that are closing or shrinking often have unrelated problems.

And even if Amazon is putting more pressure on brick-and-mortar stores, it’s not at all clear that this is the disaster Trump frames it as. A generation ago, competition from Walmart was decimating smaller retailers and retail jobs — but also lowering prices with its focus on efficiency. Amazon, by the same token, beats traditional retailers by making the process of shopping more efficient. That the President would object to this seems to reflect a view of capitalism as a zero-sum game, rather than one in which efficiency and innovation ultimately benefit everyone. It’s the same worldview that has led him to push for more restrictive international trade rules, and to defend inefficient, outdated coal-derived energy.

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As part of his multi-pronged attack, Trump has also repeatedly claimed that Amazon is gaming the system by getting preferential rates from the U.S. Postal Service. That criticism appears to be based on a 2017 Citigroup analysis, but that finding applied to all packages, not just Amazon’s. Even then, the claim relies on some selective interpretations of USPS’s cost structure. Trump’s claim that Amazon pays “little or no taxes to state & local governments” is even less rooted in reality — Amazon collects sales tax in 45 states.

So there’s room for debate over some of Trump’s criticisms of Amazon. But Trump’s last big critique is more fundamentally worrying. On Saturday, the President reiterated claims that the Washington Post, which is owned by Amazon founder and CEO Jeff Bezos, is “used as a ‘lobbyist’” that pushes Amazon’s agenda. In fact, the Post has published significant negative coverage of Amazon, and there’s no evidence that Bezos interferes with the newspaper’s coverage.

…does not include the Fake Washington Post, which is used as a “lobbyist” and should so REGISTER. 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!

— Donald J. Trump (@realDonaldTrump) March 31, 2018

That suggests Trump’s attack on the Post could be read as a more sophisticated repetition of his blunt attempts to discredit critical reporting as “fake news.” And in fact, Trump’s latest round of anti-Amazon venting came immediately after a Post report detailing multiple investigations into the Trump Organization’s finances.

There is one other possible motivation for Trump’s long-running hatred of Amazon — personal resentment of Jeff Bezos. Trump has consistently shown a deep attraction to straightforward signals of power and success. As a developer, it was famously reflected in his love of gaudy décor. As President, it has been reflected in his tall, super-wealthy, and militarized cabinet picks. For a man who sees the world in such simplified terms, it must be deeply galling to face an opponent who is as much as 40 times richer. It’s hard to imagine Trump doesn’t take some pleasure in watching that gap close every time he lambasts Bezos’s company.