As I watched President Trump call for Muslim tolerance in a cavernous Saudi palace, in front of dozens of leaders from majority Muslim countries, my stomach grew queasy.

There was nothing wrong with the goal of his much-touted speech – whose moderate tones contradicted reams of previous Trump tweets and slams at Muslims.  He was trying to rally those Sunni leaders to fight ISIS and other terrorist groups, while pledging he would confront the terrorist activities of their arch-enemy Iran.

But it was what Trump didn't say that made the speech ring false.

The president called for a united front against ISIS as he stood beside Saudi royals whose harsh brand of Islam has laid the ideological framework for Islamist extremism worldwide.

He lavished the Saudis with praise, and effusively accepted their medals, even as they continue to export that ideological poison. He praised their tolerance, even as their clerics decry Christians, Jews, and Shiite Muslims as infidels.

Yet Trump never hinted that the Saudis (and some of their Gulf allies) are fueling the same terrorist fire that he is asking them to put out.

Of course the speech made for great visuals.  The Saudis fed Trump the pomp and pageantry he admires and gave him the gift they knew he wanted – a big arms deal. They were thrilled to welcome a U.S. leader who, unlike President Obama, denounces the negative regional behavior of Iran.

But Saudi help in defeating ISIS?  The reality is far different than Trump cheered in his huge pep rally.

For starters, the Saudi monarchy is less interested in fighting ISIS than in dragging the United States into a military confrontation with Tehran.  It has proved hopelessly inept, or worse, at every military fight in which it has engaged.

In Syria, the U.S. subcontracted to the Saudis in 2012 to organize moderate Syrian Sunni rebels into a fighting force to oppose the Syrian regime.  But the Saudis financed a hodgepodge of hard-line Islamist militias that were more interested in killing Syrian moderates than fighting Bashar al-Assad, which left the way open for the emergence of ISIS.

Today, the Saudis are engaged in an air war against Houthi rebels in Yemen whom they consider to be Iranian proxies, but they have achieved little beyond bombing thousands of civilians, and dragging Washington into their fruitless battle. Their new U.S. weapons will enable them to kill more civilians.

But let's get to the glaring hole at the core of the president's oration:  the absence of any reference to the central Saudi role in the radicalizing of Islam.

The Saudis practice a fundamentalist version of Islam that is often called Wahhabism because it grew out of a long-ago deal between the founders of Saudi Arabia and the 18th century Sunni preacher Muhammad ibn Abd al-Wahhab. This religious strain scorns other faiths, detests Shiite Muslims, and praises jihad.

Indeed, Saudi Arabia forbids churches or open Christian worship within its borders, and conversion is illegal and punishable by death.

The Saudis insist Wahhabism has nothing to do with terrorism. But while this puritanical strain of Islam may not call for violence, it creates a climate of intolerance  in which violent jihadism can grow.

You can see the impact of such teachings inside Saudi Arabia – and around the world.

Nearly 2,500 Saudis have joined ISIS (not to mention the 15 out of the 19 hijackers on 9/11 who were Saudis).  And note this: the Islamic State adopted official Saudi textbooks for its schools until it was able to publish its own books by 2015.  The textbooks' hatred of non-Muslims matched the ISIS worldview just fine.

Even more disturbing, the Saudis have spent billions over the last several decades promoting their version of Islam, financing thousands of mosques, religious schools, and imams in Muslim communities all around the globe.

Farah Pandith, a Kashmiri Indian American who traveled to 80 Muslim countries as the first State Department special emissary to the Muslim world, told the New York Times:  "In each place I visited, the Wahhabi influence was an insidious presence, changing the local sense of identity; displacing historic, culturally vibrant forms of Islamic practices. …"

As a journalist who has traveled to Muslim countries around the world, my experience has been similar.  For decades I have heard moderate Muslims in places like the Palestinian West Bank, Iraqi Kurdistan, Uzbekistan, and Bosnia decry the impact of Saudi funds and teachers who spread a radical variant of Islam that undercut local teachings.  In Germany, officials worry that Saudi money will finance radical mosques that woo their new Muslim immigrants.

Saudi money has financed puritanical Islamist movements that are hardening Indonesia's more tolerant brand of Islam (the Christian governor of Jakarta was just convicted of "blasphemy"). And for decades, Saudis have financed hard-line religious schools in Pakistan that send youths to wage "holy war" in Afghanistan – or against Pakistani Shiites at home.

Moreover, tens of thousands of Egyptians, Syrians, Pakistanis, and other Muslims who have worked in Saudi Arabia for decades have absorbed this intolerant Islam and carried it back to their home countries.

Yet the drip, drip, drip of Saudi proselytizing never stops.

True, once Islamist terrorists started attacking sites inside Saudi Arabia, the Riyadh government (and other Gulf states) finally curbed much of the private – and government --  funding that went to Sunni terrorist groups.  And the Saudis have made a weak stab at changing some of their textbooks.

Moreover, Saudi intelligence has proved useful to the U.S. military in countering ISIS plots (they are arresting so many would-be terrorists at home they have plenty of candidates for interrogation).

But that all begs the central issue – the one the president ignored when he praised the opening of a new Global Center for Combating Extremist Ideology in Riyadh.

That center will be a sham unless the Saudis stop propagating their extremist version of Islam across the Muslim, and non-Muslim, world.   I hope the president is making that a condition for any future U.S. partnership with Riyadh.  Otherwise, his grandiose speech touting a U.S.-Saudi alliance against terrorism will amount to nothing more than a hollow fraud.

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