Peter Bergen is CNN's national security analyst, a vice president at New America and a professor of practice at Arizona State University. He is the author of " United States of Jihad: Investigating America's Homegrown Terrorists ."

Riyadh (CNN) Imagine Houston run by an efficient version of the Taliban, and you get an approximation of what it is like to live in Riyadh, the Saudi capital.

But to understand the significance of President Donald Trump's visit to Riyadh and his much-anticipated speech on Islam, you must also understand a bit more about the center of Saudi power.

Riyadh is a sprawling city of more than 6 million built by massive oil revenues, punctuated by soaring skyscrapers, stitched together by smooth freeways and surrounded by endless sand-colored suburbs that march ever outward to the empty deserts.

But Riyadh, despite its seemingly shiny veneer, is in trouble. For the first time in decades the Saudi monarchy can no longer rely on the revenues from oil to maintain its position as the leading Arab state and to buy off any aspirations that the Saudi population might have to play a real role in politics.

That's because the days of $100-a-barrel oil are long gone and are unlikely to return anytime soon. And it is this reality that made President Trump's trip to Riyadh and his speech on Sunday so important to the Saudi monarchy.

It's not just that they share a common interest in checking what they both regard as excessive Iranian influence in the Middle East. Both sides also see great value in the almost $110 billion arms deal signed during Trump's visit, which aims, in part, to bulk up domestic Saudi arms production and create new jobs in Saudi Arabia. And that's in addition to $55 billion in deals with US companies that were also announced during Trump's visit.

The rationale for these deals is simple -- to jump-start the Saudi economy and bring new jobs to the private sector, as Saudi Foreign Minister Adel al-Jubeir explained at a press conference on Saturday. "We expect that these investments over the next 10 years or so will provide hundreds of thousands of jobs in both the United States and in Saudi Arabia," he said. "They will lead to a transfer of technology from the US to Saudi Arabia, enhance our economy and also enhance the American investments in Saudi Arabia, which already are the largest investments of anyone."

When oil wealth seemed an endless spigot of gold, the absolute Saudi monarchy created, somewhat paradoxically, a quasi-socialist state: an astonishing 90% of Saudis work for the government and have long enjoyed subsidies for water, electricity and gas. Health care and education are free.

But, in late 2015, the IMF warned that, given falling oil prices, the Saudi government could run out of financial reserves in five years if it kept up its present rate of spending.

With oil prices holding steady at around $50 a barrel , the Saudi government is now cutting government salaries and reducing subsidies. Trump's visit -- and deals -- therefore create a critical opportunity in the private sector for Saudis who can no longer exclusively depend on the government.

King Salman -- who became King in 2015 and for almost five decades was the governor of Riyadh, overseeing its explosive growth from a city of a few hundred thousand in the mid-1960s to the massive city it is today -- has empowered his 31-year-old son, the Deputy Crown Prince Mohammed bin Salman, to also play a role in addressing Saudi's immediate demands. He is charged with modernizing Saudi society slowly and diversifying the Saudi economy quickly.

The Saudi government calls it " Vision 2030 ." The aim is to privatize the education, health care, agriculture, mining and defense sectors and to sell off Saudi Aramco, perhaps the wealthiest company in the world, which is estimated to be worth around a trillion dollars . The Saudis expect the United States to be a key player in all this, particularly given Trump's expertise in corporate America.

And the time is ripe for the Saudi monarchy to begin to transform its economic base. Its country is both young and incredibly connected -- 70% of the population is under 30, and 93% of Saudis use the Internet, far more than in the United States.

The declining role of the religious police

Riyadh sits in the Nejd heartland of Saudi Arabia, where in the mid-18th century the first Saudi King allied with Muhammad bin Abdul-Wahhab, a cleric who promoted a harsh interpretation of Sunni Islam.

This alliance is a marriage of convenience that has survived for more than two and half centuries and is the key to the political economy of Saudi Arabia in which the Saudis have retained absolute authority -- so much so that their family name is embedded in the name of the country -- while the Wahhabi religious establishment sanctions the rule of the absolute monarchy and has largely held sway over the social mores of Saudi society.

Until a year ago, compliance with the dictates of Saudi-style Wahhabi Islam were rigorously enforced by members of the feared religious police, known as the Committee for the Promotion of Virtue and the Prevention of Vice (the same name that was used by the Taliban's religious police when the Taliban were in power in Afghanistan).

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The religious police patrolled the streets looking for purported malefactors and were given a more or less free hand to do so. In one notorious episode in 2002, in the holy city of Mecca, the religious police prevented girls from fleeing a school that was on fire because they were not properly dressed. Fifteen of them perished in the flames.

But, last April, the wings of the religious police were clipped by King Salman and his son MBS, as he is universally known here. They no longer have the power to arrest suspects and now can only report them to regular police units.

In addition to getting the religious police to back off, the Saudi monarchy has allowed some music concerts to happen, but their biggest ambition, as described above, is to wean Saudi Arabia from its almost total dependence on oil revenues.

The Saudis see the Trump administration as a key to this, and that's why they rolled out the reddest of red carpets for the President's visit.

In return, Trump received the perfect platform to give his speech on Islam. After all, where better to make that speech than in the holy land of Saudi Arabia, home to the sacred cities of Mecca and Medina? And who better to convene the leaders of every Muslim country to hear Trump speak than the Saudi royal family?

The speech

In Riyadh, the city where Osama bin Laden was born six decades ago, President Trump delivered his much-anticipated speech Sunday to leaders from around the Islamic world.

The stakes needless to say were high. Candidate Trump had previously opined that "Islam hates us" and had called for "the total and complete shutdown of Muslims entering the United States," an argument he has since modified and moderated.

Nonetheless, such rhetoric on the campaign trail made Trump an unpopular figure across the Muslim world. A poll released in early November ahead of the US presidential election found that only 9% of those polled in the Middle East and North Africa would have voted for Trump versus 44% for Hillary Clinton.

After he was elected, Trump had also attempted to ban temporarily travel from a half dozen Muslim countries to the United States, an order that was midwifed by a top policy adviser, Stephen Miller, who now had the unenviable task of also being the "lead pen" for the President's keynote speech on Islam.

Trump's speech was billed as a "reset" with the Muslim world, just as President Obama's was eight years ago when he went to Cairo and declared "I have come here to seek a new beginning between the United States and Muslims around the world; one based upon mutual interest and respect..."

During the presidential campaign in August, Trump panned Obama's Cairo speech, castigating Obama for a "misguided" speech that didn't condemn "the oppression of women and gays in many Muslim nations, and the systematic violations of human rights, or the financing of global terrorism..."

Of course, it's all a lot more complicated when you are President, and Trump raised none of these issues in his Riyadh speech, instead emphasizing the scourge of terrorism, which is something that pretty much anyone in the Islamic world and the West can agree upon.

Trump did use the term "Islamic terrorism," which critics assert conflates Islam with terrorism, but his speech, which was received with polite attention from the leaders of the Muslim world, was a largely anodyne account of the need for civilized countries to work together to defeat terrorist groups in the name of our common humanity and -- minus some swipes at Iran -- could have been delivered by President Obama.

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Speeches, of course, are not policies, and Obama's initial popularity in much of the Muslim world waned after he ordered a large surge of troops into Afghanistan, greatly ramped up drone strikes in Pakistan and Yemen and failed to intervene in any meaningful way to end the Syrian civil war.

The same surely will hold true for Trump. If his administration continues to pursue its travel ban from six Muslim-majority countries in the courts and does little to bring peace to the Middle East, whether in Syria or between the Israelis and the Palestinians, any bump he might get from his Riyadh speech will prove as ephemeral as the sandstorms that occasionally blast through the Saudi capital.

But even if Trump's speech does not herald any real changes in US national security policies, the business deals that the Trump administration is helping to broker with the Saudis will help move the Saudi economy away from its total dependence on oil.