Donald Trump has his sights set on Amazon. He is reportedly “obsessed” with the internet commerce giant, and as is his wont, spent Thursday morning tweeting about it. And it’s not because he loves online shopping.

“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!” he said. Trump is allegedly mulling using antitrust measures to knock Amazon down a notch.

Like so many of Trump’s governing impulses, his focus on Amazon probably has more to do with a personal grudge than any principle. He has a well-documented history of attacking the company due to the fact that its CEO, Jeff Bezos, also owns the Washington Post, which has been a thorn in the side of the administration on many a story.

That doesn’t mean Amazon’s economic and political power isn’t a real problem, however. Trump’s motivation is bad and his grasp of the facts worse, but it’s true that Amazon’s ability to influence the market is an issue that needs a solution.

Concerns about Amazon’s capacity to strangle competitors are nothing new, of course, dating back to its big-footing of publishers in the book market, which was its early claim to fame. But those worries have only been magnified in recent years by Amazon’s growing dominance of all online shopping and, now, with its acquisition of the Whole Foods grocery chain, its move into actual brick-and-mortar retail.

Currently, more than half of online shopping searches begin directly on Amazon, and it is responsible for more than 40% of all internet retail sales. It simply dwarfs all comers in that space. And it’s involved many other kinds of business too, from data management to entertainment.

Plus, Amazon has certain advantages that other businesses don’t. While Trump generally bungles the particulars when he rants about Amazon’s tax treatment, it is true that third-party sellers who use Amazon do not have to collect sales tax, giving them a leg up over Main Street stores. It’s also true that the company may have a sweet deal with the US Postal Service.

This market power translates into political power for Amazon. Just look at how the company’s search for a second headquarters location is shaping up, with city and state lawmakers offering loads of tax breaks and other goodies to a company that already pulls in obscene amounts of money. Maryland, for instance, is on track to offer some $5.6bn in incentives for Amazon to bring its new headquarters there; in New Jersey, it’s $7bn.

Some cities even want to direct taxes raised from Amazon back to Amazon, or allow it to provide input over where and how tax dollars are spent, abdicating a main government role to a private company. Amazon is so big and powerful that it has politicians all over the country asking “how high?” when it says “jump!” And not for nothing, Amazon already benefits from substantial public subsidies.

His focus on Amazon is certainly not the only economic area in which Trump’s less than admirable motivations point him in the right direction. His distaste for CNN could very well have driven the administration to rightfully challenge the proposed merger between Time-Warner and AT&T. On trade, his inability to grasp specific details and bizarre belief that the whole thing is a zero-sum game are still leading him to question a legitimately broken global trade order.

Depending on how this all shakes out then, a positive outcome could emerge from one of Trump’s ridiculous grudges, as Amazon definitely needs to be reined in. Given the chaotic state of the administration, such inadvertent progress is probably the best for which we can hope.

• Pat Garofalo is a writer and editor based in Washington. He is working on a book about taxes and corporate power