We don’t often find ourselves agreeing with Democratic attorneys general, but the AGs of Maryland and D.C. have a point this time around.

While their emoluments lawsuit against President Trump is based on zero precedent and novel interpretations of the Constitution, they at least have good ethics on their side. President Trump’s worldwide business empire creates conflicts of interest that the president of the U.S. shouldn’t have.

Maryland’s Brian Frosh and D.C.’s Karl Racine have made it very clear that they see the state attorney general’s primary job as a tool of the #Resistance. Frosh, for instance, has entered Maryland into a frivolous lawsuit over the new cap on deducting state and local income taxes (taxes are very high in Maryland).

But last week, a federal judge ruled that a suit brought against Trump by D.C. and Maryland could go forward. The suit argues that Trump International Hotel in D.C. puts Trump in violation of the Constitution’s emoluments clause. A central question at the heart of this case is whether a foreign government paying Trump’s hotel (which he owns) to host an event is giving Trump an “emolument.” Separate from that question is whether such a payment is proper. On the latter question, the answer is clearly no.

The president should not operate businesses that put him in the position to be greatly enriched by foreign governments and foreign powers. The Trump International Hotel in D.C. isn’t his only such business.

China’s largest state-owned bank, the Industrial and Commercial Bank of China, is a tenant at Trump Tower. So, every time Trump is dealing with China, he is potentially enriching, alienating, or squeezing his tenant. We know how China plays economic hardball, applying very precise pressure. Trump exposing himself to this sort of coercion harms his ability to lead with the country’s best interest at heart.

And finally, Trump’s businesses simply create an appearance of impropriety. There’s no need to give ammunition to the folks trying to find Putin-Trump conspiracy theories.

All the reasons above don’t mean Trump’s businesses are illegal. They do mean Trump’s business holdings interfere with his ability to be president of the U.S., which is a pretty important job.

He ought to arrange for blind sales of his properties by a broker and put the proceeds in a blind trust, and he should suspend the business of licensing out his name until after he leaves office.

But not everything that’s legal is ethical.