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Saudi Arabia's crown prince, Mohammed bin Salman, arrives in Washington on Monday to kick off a two-and-a-half week visit to the United States. It's hardly his first trip to America, but it will certainly be the most momentous.

Within the space of a few years, the 32-year-old prince has installed himself as Saudi Arabia's surprise heir apparent, purging senior relatives from the line of succession and cowing other rivals. Most observers already see Mohammed bin Salman — often referred to by his initials, MBS — as the de facto ruler of the kingdom, simply waiting for the moment his aging father, King Salman, chooses to move aside.

In myriad conversations with Western media, Mohammed bin Salman presents himself as a young man in a hurry, shaking up a country whose leadership is better known for its caution and conservatism. He has already made dramatic social changes: Women will soon have the right to drive, movie theaters are opening up and the powers of the once-ubiquitous religious police are being curbed. He also spearheaded a sweeping purge of elites that targeted supposedly corrupt officials and tycoons — while further consolidating his own grip on power.

He is styled by confidants as a cross between a ruthless, reformist autocrat akin to Singapore's Lee Kuan Yew and a tech-giant “disrupter” (Silicon Valley will feature prominently among his stops). He wants to restructure the Saudi economy and wean it off its decades-long dependence on oil wealth. He wants to shock the system: “You have a body that has cancer everywhere, the cancer of corruption. You need to have chemo, the shock of chemo, or the cancer will eat the body,” the crown prince told my colleague David Ignatius last month.

Critics point to the myriad rights abuses and lack of democracy that still characterize Saudi politics. “If his modernizing is working, why does he need to imprison peaceful advocates of modernization?” The Washington Post's editorial page asked last week, referring to dozens of political prisoners still behind bars. But Mohammed bin Salman's defenders urge patience as he gets to work.

“The key factor to look at is that for the first time in 40 years, a bold leader has emerged in Saudi Arabia, determined to face all the challenges previous leaders have been kicking down the road for decades,” wrote Ali Shihabi, the executive director of the Arabia Foundation, a Washington-based think tank close to Riyadh. “MBS is determined to upend 50 years of incremental, quietist and often reactionary policymaking. As a result, the 32-year-old crown prince has launched a relentless quest to offset decades of lethargy and inaction by his elders so he can drag his country into the 21st century.”

But if the crown prince strikes many as a fascinating agent of change, he also occupies a familiar role in the Western imagination. “MBS fits the model of the west’s favorite partners in the Middle East: regime reformists, who promise change but not too much of it. Here is an apparently anti-establishment leader who hails from the very heart of the establishment,” Jane Kinninmont, a Persian Gulf expert at Chatham House, wrote in a new article for Britain's Prospect magazine. “Even while he consolidates his power in the center of a deeply autocratic system, he has adopted a discourse of youth empowerment, portraying the Saudi population as dynamic, entrepreneurial and creative.”

Kinninmont warned that Mohammed's ascent could just as easily prefigure a dramatic fall: “Over the past year, Saudis have witnessed a series of once unquestionable power centers turn out to be chimeras, leading people to question their established beliefs more generally. If the young Crown Prince’s reforms fail, will they start questioning MBS himself?”

The prince is indeed playing a risky game. His domestic moves have won widespread plaudits in Washington and elsewhere, but his actions overseas have proved far more controversial.

When Mohammed meets with President Trump at the White House on Tuesday, they'll probably see eye-to-eye on Iran, Riyadh's longtime foe and Trump's geopolitical bete noir. Reports indicate that the Trump administration will probably pull out of the nuclear deal with Iran in May, possibly triggering a confrontation with the Islamic Republic that would be cheered in Saudi Arabia.

Beyond that, things get trickier. Mohammed is the architect of a devastating Saudi-led intervention in Yemen, which has contributed to a horrific humanitarian crisis and prompted growing criticism on Capitol Hill. He also helped trigger the ongoing Persian Gulf crisis with Qatar — apparently with carte blanche from the White House — that has largely backfired, doing little to boost Saudi prestige and exposing profound splits within the Trump administration. And he'll have to reckon with Trump over the zombie state of the Israeli-Palestinian peace process, a situation made all the worse by Trump's recognition — publicly opposed by Riyadh — of Jerusalem as Israel's capital

The Post's Missy Ryan explains who the key players are in the conflict in Yemen and why the United States is supporting Saudi Arabia there. (Sarah Parnass, Kareem Fahim/The Washington Post)

Then there’s the dilemma posed by Trump. After clashing with President Barack Obama, the Saudis were conspicuous cheerleaders when Trump came to power. The crown prince is said to have built a close relationship with Jared Kushner, Trump’s son-in-law and jack-of-all-trades adviser. But with Kushner  at the center of overlapping scandals and every day in the White House seemingly an exercise in chaos, there's a chance the Saudis are depending too much on one person.

“Trashing Obama, a Saudi favorite pastime, is not a smart long-term approach to a democracy,” wrote Bruce Reidel of the Brookings Institution. “The Saudi strategy toward America is built fundamentally on the Trump family connection, expensive lobbyists and Iran bashing. The prince has little experience with the complexities of America’s politics, which are more complicated than ever in the Trump era.”

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