President Trump is out of control. It’s time for an intervention.

The intervention should come from Defense Secretary Jim Mattis, Secretary of State Rex Tillerson, Secretary of Homeland Security John Kelly, National Security Advisor H.R. McMaster and Attorney General Jeff Sessions.

Their message to Trump should be blunt: Unless he starts acting presidential, stops undermining them, seriously curtails his tweeting, and learns and respects basic ethical guidelines, they will all resign together while warning the country that the president is temperamentally (and perhaps intellectually) unfit for office.

Kelly and Sessions, both big believers in Trump’s mission to heavily vet visitors from terrorist-haven nations, should be incensed that Trump’s tweets are undermining the carefully-prepared legal case designed to garner the Supreme Court’s approval of Trump’s so-called “travel ban.”

Sessions should be furious that Trump’s paranoia about the Russian investigation has created so many unnecessary distractions from the important business of reforming the Justice Department — and he should be outraged that Trump has yet to submit nominees for so many key DOJ positions, leaving Sessions badly short-handed.

Sessions should further make clear how improper it was for the president to demand FBI Director James Comey’s private audience to talk about the Russian probe, not to mention specifically urging Comey (reportedly) to go easy on former national security adviser Mike Flynn.

As for Tillerson, Mattis, and McMaster, they should still be fuming about Trump’s reported deletion, while in Europe, of a carefully-crafted speech line explicitly re-affirming United States commitment to NATO’s crucial Article 5, which says an attack on any one NATO nation will be met with a combined defense from all.

This isn’t just some technical point of diplomacy. This is a matter of freedom for millions of people and, worse, a potential trip-wire for World War III.

Until this year, Russia knew it dared not use its military in any way against the Baltic states of Latvia, Lithuania and Estonia — because as powerful as Russia is, it cannot withstand the might of a U.S.-led NATO. With the Baltic states being NATO members, Article 5 would ensure a full counter-response to Russian aggression. By assuring such a response, it deters the transgression in the first place.

Trump’s repeated refusal (for nearly a full year now) to re-affirm Article 5 does just the opposite: His ambiguity on Article 5, combined with his whole panoply of bizarrely pro-Russian fulminations, invites Russian aggression of the same sort as Moscow’s absorption of the Crimean peninsula and incursions into eastern Ukraine. Yet if Russia does so transgress against the Baltic states, Europe surely would demand a response anyway. A series of skirmishes could lead to a wider conflagration. There lies disaster.

That’s why Tillerson, Mattis and McMaster reportedly were so insistent that Trump re-commit to Article 5. And, when he absolutely blind-sided them by not committing, he destabilized all of NATO, to Russia’s advantage.

Granted, there are times when presidents are right to insist on having their way in speeches. Witness President Ronald Reagan’s repeated re-insertions of the key lines in his famous “Evil Empire” speech and his galvanizing demand, “Mr. Gorbachev, tear down this wall.”

Reagan was not only right on substance in those cases while Trump is wrong, but Reagan also was right on process. As much as the diplomats tried to water down his language, he at least made clear to all his aides, before the speeches in question, what he would say. An administration must speak in one voice, not just for good form, but because diplomatic and military confusion can cost lives.

Trump’s free-wheeling, leaving his key Cabinet members in the dark, was reckless in a way Reagan’s firm insistence never was.

Trump’s impetuosity is not just a stylistic tic — it carries real-world consequences, most of them bad.

For a lesser example, some of his statements made it harder for the House to pass healthcare reform.

Worse, Trump’s threat to withdraw funding for our military base in South Korea required McMaster to scramble to walk it back – and, quite arguably, added impetus to the election of a less-pro-American president in South Korea. And, of course, Trump’s loose lips quite possibly helped reveal information to Russia that compromised anti-Isamic State intelligence sources.

In short, Trump’s lack of discipline is dangerous. It puts our country and its assets at risk. His five top ministers should tell him that if he won’t rein himself in, they will put their collective reputations against his. His presidency would not survive.

Quin Hillyer (@QuinHillyer) is a contributor to the Washington Examiner’s Beltway Confidential blog. He is a former associate editorial page editor for the Washington Examiner.

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