President Trump reminds me of Winston Churchill’s quip about the Germans: He’s either at your throat or at your feet.

During his trip to Saudi Arabia in May, Trump praised Qatar as a “crucial strategic partner”—it hosts a major U.S. airbase that is a hub for air strikes against ISIS—and had what was, by all accounts, a warm meeting with the emir of Qatar, Tamim bin Hamad Al Thani.

“We are friends, we’ve been friends for a long time now, haven’t we?” Trump told reporters after their get-together.  “Our relationship is extremely good, we have some very serious discussions right now going on, and one of the things that we will discuss is the purchase of lots of beautiful military equipment because nobody makes it like the United States. And for us, that means jobs, and it also means frankly great security back here, which we want.”

On Tuesday, it was a different story. Trump unleashed a series of withering tweets—his weapon of choice—against the small, immensely rich Persian Gulf kingdom. In the process, he celebrated the decision by Saudi Arabia, the United Arab Emirates, Bahrain, and Egypt to cut off diplomatic and economic contacts with Qatar in protest over its ties to Iran and to Sunni extremist groups such as the Muslim Brotherhood.

Said the president on Twitter:  “During my recent trip to the Middle East I stated that there can no longer be funding of Radical Ideology. Leaders pointed to Qatar – look! … So good to see the Saudi Arabia visit with the King and 50 countries already paying off. They said they would take a hard line on funding … extremism, and all reference was pointing to Qatar. Perhaps this will be the beginning of the end to the horror of terrorism!”

To say that this is a head-snapping change of direction is to put it mildly. The surprise is all the greater because Trump’s message of support for the Saudis’ anti-Qatar position is at odds with what his secretary of state and defense are saying. They maintained a tone of studious neutrality, with Tillerson saying at a press conference in Australia, “We certainly would encourage the parties to sit down together and address these differences.”

Mattis, for his part, expressed confidence that this tiff would not affect the fight against ISIS. “I am positive there will be no implications coming out of this dramatic situation at all, and I say that based on the commitment that each of these nations that you just referred to have made to this fight.” Mattis might want to recalibrate his calculations now that Trump’s tough line potentially endangers the future of the al-Udeid Air Base and, more generally, calls into question the value of an American alliance of the kind that Qatar has cultivated for years.

That’s not to deny that Qatar’s critics, from Riyadh to the White House, have a point. Qatar has been a highly problematic ally—just like Saudi Arabia, Turkey, Egypt, and other nondemocratic states that Trump has praised in hyperbolic terms in recent months.

Qatar has chosen to play both sides of the street to assure its survival. This is hardly a unique strategy: Pakistan receives U.S. aid while sponsoring the Taliban insurgency, which has killed many American soldiers. Saudi Arabia, for its part, is a valuable American partner in the war on terror–but also a tireless proselytizer for the Wahhabi strain of Islam which has produced countless terrorists.

In Qatar’s case, it provides Islamist extremists a wide audience on its state-sponsored TV channel, Al Jazeera, and it directly supports repugnant groups such as Hamas. At the same time, Qatar hosts a major U.S. air base and 10,000 U.S. military personnel and provides a forum where U.S. officials can engage in quiet talks with groups such as the Taliban.

Qatar’s double game has long angered its Gulf neighbors. Apparently, they went ballistic after reports that Qatar had paid a billion-dollar ransom to Iran and to an al-Qaeda affiliate in Syria in order to win the release of Qatari royals taken hostage in Iraq and of militiamen captured in Syria.

It makes sense for the U.S. and its other allies in the region to pressure Qatar to stop playing footsy with Islamist extremists and with Iran. But there is little sign in this week’s events that Trump is pursuing a carefully considered strategy that utilizes a whole-of-government approach. The president should have been pressing Qatar to mend its ways behind-the-scenes, rather than professing eternal friendship in a meeting with Qatar’s emir and then blowing up on Twitter. Given the high stakes involved, this is a time for carefully calibrated diplomacy, not social-media grandstanding.