WASHINGTON — Having coined Bush Derangement Syndrome more than a decade ago, I feel authorized to weigh in on its most recent offshoot. What distinguishes Trump Derangement Syndrome is not just general hysteria about the subject, but additionally the inability to distinguish between legitimate policy differences on the one hand and signs of psychic pathology on the other.

Take Trump’s climate-change decision. The hyperbole that met his withdrawal from the Paris agreement — a traitorous act of war against the American people, America just resigned as leader of the free world, etc. — was astonishing, though hardly unusual, this being Trump.

What the critics don’t seem to recognize is that the Paris agreement itself was a huge failure. It contained no uniform commitments and no enforcement provisions. Sure, the whole world signed. But onto what? A voluntary set of vaporous promises. China pledged to “achieve the peaking of CO2 emissions around 2030.” Meaning that they rise for another 13 years.

The rationale, I suppose, is that developing countries like India and China should be given a pass because the West had a two-century head start on industrialization.

I don’t think the West needs to apologize — or pay — for having invented the steam engine. In fact, I’ve long favored a real climate-change pact, strong and enforceable, that would impose relatively uniform demands on China, India, the U.S., the EU and any others willing to join.

Paris was nothing but hot air. Withdrawing was a perfectly plausible policy choice (the other being remaining but trying to reduce our CO2-cutting commitments). The subsequent attacks on Trump were all the more unhinged because the president’s other behavior over the last several weeks provided ample opportunity for shock and dismay.

It’s the tweets, of course. Trump sees them as a direct, “unfiltered” conduit to the public. What he doesn’t quite understand is that for him — indeed, for anyone — they are a direct conduit from the unfiltered id. They erase whatever membrane normally exists between one’s internal disturbances and their external manifestations.

For most people, who cares? For the president of the United States, there are consequences. When the president’s id speaks, the world listens.

Consider his tweets mocking the mayor of London after the most recent terror attack. They were appalling. This is a time when a president expresses sympathy and solidarity — and stops there. Trump can’t stop, ever. He used the atrocity to renew an old feud with a minor official of another country. Petty in the extreme.

As was his using London to support his misbegotten travel ban, to attack his own Justice Department for having “watered down” the original executive order (ignoring the fact that Trump himself signed it) and to undermine the case for it just as it goes to the Supreme Court.

As when he boasted by tweet that the administration was already doing “extreme vetting.” But that explodes the whole rationale for the travel ban — that a 90-day moratorium on entry was needed while new vetting procedures were developed. If the vetting is already in place, the ban has no purpose. The rationale evaporates.

And if that wasn’t mischief enough, he then credited his own interventions in Saudi Arabia for the sudden squeeze that the Saudis, the UAE, Egypt and other Sunni-run states are putting on Qatar for its long-running dirty game of supporting and arming terrorists (such as the Muslim Brotherhood and Hamas) and playing footsie with Iran.

It’s good to see our Sunni allies confront Qatar and try to bring it into line. But why make it personal — other than to feed the presidential id? Gratuitously injecting the U.S. into the crisis taints the endeavor by making it seem an American rather than an Arab initiative and turns our allies into instruments of American designs rather than defenders of their own region from a double agent in their midst.

And this is just four days’ worth of tweets, all vainglorious and self-injurious. Where does it end?

The economist Herb Stein once quipped that “if something cannot go on forever, it will stop.” This really can’t go on, can it? But it’s hard to see what, short of a smoking gun produced by the Russia inquiry, actually does stop him.

Trump was elected to do politically incorrect — and needed — things like withdrawing from Paris. He was not elected to do crazy things, starting with his tweets. If he cannot distinguish between the two, Trump Derangement Syndrome will only become epidemic.

Charles Krauthammer is a columnist with The Washington Post. His email address is: letters@charleskrauthammer.com.