On Monday, Saudi Arabia and three of its allies cut off diplomatic and economic relations with Qatar, a tiny, energy-rich emirate in the Persian gulf. The Saudis moved to punish and isolate Qatar for its support of Islamist groups and its refusal to go along with a Saudi-led campaign against Iran. By Tuesday, Donald Trump took to Twitter – and he made the crisis between two US allies a lot worse.

In a series of morning tweets, Trump took credit for instigating Saudi Arabia and its allies to sever relations with Qatar and to impose a blockade, sealing the emirate’s only border and cutting off air and sea travel.

He mentioned his visit to Saudi Arabia last month, where he called on a gathering of Arab and Muslim leaders to isolate Iran and to cut off funding for extremist groups. “During my recent trip to the Middle East I stated that there can no longer be funding of Radical Ideology,” Trump wrote. “Leaders pointed to Qatar — look!”

Instead of offering to play peacemaker, as two of his top national security aides had done hours after the crisis erupted, Trump unequivocally sided with Saudi Arabia and its main ally, the United Arab Emirates.

Clearly, Saudi leaders are playing Trump, exploiting the grandiose reception they gave him last month after he decided to make the kingdom the first stop on his maiden foreign trip as president. By the end of his two-day visit, Trump had become Saudi Arabia’s cheerleader and he aligned US foreign policy with the kingdom’s vision of the Middle East.

In a 21 May speech to nearly 50 Arab and Muslim leaders gathered in Riyadh, the Saudi capital, Trump framed the region’s problems as solely due to Iranian aggression and terrorism by Islamist extremist groups. “From Lebanon to Iraq to Yemen, Iran funds, arms, and trains terrorists, militias, and other extremist groups that spread destruction and chaos across the region,” Trump said, echoing the harsh comments of Saudi leaders. “For decades, Iran has fueled the fires of sectarian conflict and terror.”

The Saudis read Trump accurately from the time he took office – they understood that he craved flattery and respect. Arab leaders, especially the oil-rich monarchs, are used to flattery since they live with it every day. So the Saudis decided to give Trump an extravagant welcome, the kind of deference he would never get at home.

The streets of Riyadh were filled with billboards of Trump and Saudi King Salman. The Ritz-Carlton hotel, where the president and his entourage stayed, projected a portrait of Trump onto its exterior, stretching for five floors. Most of all, Saudi leaders convinced Trump that they value and respect him far more than his predecessor, Barack Obama.

And the kingdom’s investment in wooing Trump is paying off. It’s not surprising that Trump would offer unqualified support to Saudi Arabia in its conflict with Iran, since the president and many of his advisers consider Iran the greatest threat to US interests in the Middle East.

But with his criticism of Qatar, which is a longtime American ally and home to the largest US military base in the region, Trump is telling the Saudis that he will side with them in virtually every regional conflict. In Trump’s eyes, the Saudis can do no wrong.

Trump is also undermining members of his own administration, who have tried to stick to the traditional US policy of avoiding publicly taking sides in the regional feuds among Arab allies in the Gulf.

On Monday, hours after the Saudis announced their campaign to isolate Qatar, the US secretary of state, Rex Tillerson, and the defense secretary Jim Mattis hinted that they would try to mediate between the two US allies. “We certainly would encourage the parties to sit down together and address these differences,” Tillerson said.



But Trump, with his usual bravado, torpedoed any attempt at the US serving as an honest broker. “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,” Trump tweeted on Tuesday. He added: “Perhaps this will be the beginning of the end to the horror of terrorism!”

For years, Qatar has provided funds and support to the Muslim Brotherhood, Hamas and extremist groups in Syria, Libya and elsewhere. But other Arab monarchies, including Saudi Arabia, also have a record of supporting extremists.

Beyond the current crisis with Qatar, Trump’s unequivocal support has emboldened a newly assertive Saudi Arabia. For decades, the kingdom pursued a largely behind-the-scenes foreign policy that benefited from booming oil prices. Saudi leaders exerted their power by funding proxies and friendly governments, while the kingdom avoided direct military intervention. But today, King Salman and his advisers are becoming more aggressive militarily, most notably by launching a war in Yemen in March 2015.

On Tuesday, when the Saudi foreign minister, Adel al-Jubeir, was asked if the kingdom and its allies would take “military measures” if Qatar doesn’t relent, he replied: “I hope not.”

Thanks to Trump’s carte blanche, Saudi Arabia has little incentive to change course before it can force its smaller neighbor into submission.