Just a few years ago, Saudi Arabia and its oversized royal family faced a conundrum.

With the ascension of Salman bin Abdulaziz Al Saud at the age of 79 in January 2015, it confirmed that the Saudis weren’t yet prepared to turn over the reigns of government from the legendary second generation of sons of Ibn Saud, generally seen as the founder of the modern Saudi state. Salman, the 25th son of Ibn Saud, ascended the throne, while Muqrin bin Abdulaziz Al Saud, an even younger brother, became crown prince. Not long ago, it was conventional wisdom that Saudi Arabia had become a gerontocratic horizontal monarchy where power passed from brother to increasingly infirm brother, with no plan for transitioning to a younger monarch.

Salman, now 81, who effectively governed the country was rumored to be suffering from Alzheimer’s disease when he ascended the throne. Today, however, he presides over a kingdom that’s taken a much more muscular role regionally, from a devastating proxy war in Yemen against Houthi rebels and former president Ali Abdullah Saleh(and, really, against Iran) to a deepening diplomatic crisis with Qatar over its alleged funding of Islamic terrorism (including  relatively pro-democratic groups like Hamas and the Muslim Brotherhood), despite the Saudi kingdom’s own funding of hard-line Wahhabists.

* * * * *

RELATED: Why Trump’s outreach to Saudi Arabia
might not be so clueless

* * * * *

But within three months, he had replaced Muqrin as crown prince from a member of the next generation — the revered interior minister Muhammad bin Nayef bin Abdulaziz Al Saud, now 57 years old, the deputy crown prince who became a beloved Saudi figure among American policymakers in the 2000s and early 2010s for his effectiveness in Saudi counterterrorism efforts that proved largely successful (by either bribing and rehabilitating would-be jihadists or eliminating them).

In recent years, there were reports that Muhammad bin Nayef, who suffered ill effects from a 2009 assassination attempt, was in increasingly ill health.

That may have been an issue in Salman’s decision today in removing Muhammad bin Nayef, both as interior minister and crown prince. Instead, Salman’s own son, the 31-year-old Muhammad bin Salman Al Saud, who replaced his father as the Saudi defense minister upon his father’s ascension to the throne in January 2015, will now be elevated as crown prince. In the last two and a half years, Muhammad bin Salman’s star has been on the rise, just as Muhammad bin Nayef’s star has been on the wane. His tenure as defense minister hasn’t always been smooth, given the aggressive and sometimes over-hasty steps he took in 2015 to intervene in Yemen before his country’s security services and armed forces seemed ready to carry out his plans. But no one paying attention could have missed the ambition of the king’s son.

Though ‘MbN,’ who was educated abroad, has long been a favorite of the US military and intelligence elite, ‘MbS’ has increasingly been a favorite of the five-month Trump administration. That’s not a small consideration, given that Trump chose Saudi Arabia to be the first foreign country that he visited as US president. But whereas MbN has spent nearly two decades traveling the globe and reassuring Saudi allies abroad, MbS has spent much of his life in the shadows of his father, who served as governor of Riyadh province in the center of the country (and the second-most populous province) from 1963 to 2011. He was educated domestically, at King Saud University in Riyadh, and his English language skills aren’t as sharp as some of his fellow princes. Before his elevation as deputy crown prince two years ago, even Saudis knew virtually nothing about him. Today, he’s a ubiquitous presence in his father’s government and the very public face of the Saudi offensive — critics would say quagmire — in Yemen, and he’s been central to the Saudi effort to corral allies in the Gulf Cooperation Council, such as Bahrain and the United Arab Emirates, as well as Egypt, in isolating Qatar.

MbS has talked nearly as aggressively about economic reform — partially privatizing Saudi Aramco, the national oil and gas company, and streamlining the bloated Saudi bureaucracy in favor of markets and even opening Saudi Arabia to foreign investment. He is spearheading the rollout of a new value-added tax that will take effect in January 2018, and of diversifying the Saudi economy, for so long dependent on oil and gas revenues.

But in elevating his own son — breaking a taboo going back decades to the death of Ibn Saud — Salman has engineered a warp-speed solution to the ‘Saudi succession crisis’ that almost no one imagined. For 64 years, Ibn Saud’s children have run Saudi Arabia. Now, Salman is skipping over the generation of Ibn Saud’s more seasoned grandchildren and putting the future of the region’s chief Sunni power in the hands of someone who might as well come from among Ibn Saud’s great-grandchildren instead. In less than 30 months, Saudi Arabia has gone from a having a crown prince older than Donald Trump to having a crown prince younger than Kim Jong-un.

It’s too soon to know exactly what to make of the breakneck speed of the Saudi transition. Saudi politics (and yes, even autocratic kingdoms have politics) are undemocratic and opaque to those outside the Saudi royal family — and that goes double for foreign observers. But it’s clear that change is coming to the kingdom, and it’s coming so fast that a new and relatively unknown generation is now on the cusp of taking power. If the past two years are any indication, the future of the Saudi monarchy seems set to take an increasingly interventionist course — even as it weathers a global oil price depression, the rise of renewable energy sources and a crushing wave of global criticism over its human rights abuses.

It may be that the Saudi royals, in embracing generational change, are finally taking to heart the warning of the former Dubai emir, Rashid bin Saeed al Maktoum: ‘My grandfather rode a camel, my father rode a camel, I drive a Mercedes, my son drives a Land Rover, his son will drive a Land Rover, but his son will ride a camel.’

Yet, even as MbS has indicated he understands the unreformed Saudi state must change in order to survive, he has also shown that he’s willing to shake up a long-simmering regional cold war with Iran’s Shiite Islamic Republic, as well as swat down democratic and liberalizing threats within the Sunni Muslim world.

It’s now more likely than not that MbS will inherit the Saudi throne at a much younger age than any of his predecessors. Whether he’ll do so as an internal reformist or as a regional misadventurer is still anyone’s guess.