Though the decision was not difficult to predict, it nonetheless marks a major milestone in the country's history. It also carries far-reaching implications for a restive Middle East and for the rest of the world.
The already-powerful Prince Mohammed (known as MBS) -- who will retain his position as defense minister and add to that a new one of deputy prime minister -- has spearheaded an ambitious and daring program of reforms.
He is seeking to transform his country, both internally and externally, replacing a long tradition of slow social and economic change and low-key diplomacy with an assertive set of reform plans and a foreign policy that have produced both excitement and unease at home and abroad.
Now that he is officially the man who will become king, his plans will become more energized, and his moves beyond Saudi Arabia's borders, particularly regarding Saudi Arabia's bitter rival, Iran, will also likely gain strength.
If ever there were a country in need of modernization, Saudi Arabia is it. The prince is deeply committed to carrying major reforms to fruition. He embodies dynamism, youthful boldness and a vision of possibility. But the far-ranging changes he is bringing to the conservative kingdom and to the region carry risk and no guarantee of success.
In a region roiled with instability, they add another element of uncertainty.
Mohammed's 81-year-old father, King Salman, plucked his young son from relative obscurity just days after he ascended the throne two years ago. Until then, MBS had managed his father's crown prince court. Once in power, Salman propelled
Mohammed bin Salman to ever more powerful positions.
He named him minister of defense when he was just 29, made him deputy crown prince, and placed him in charge of a new economic council charged with the daunting task of saving the Saudi economy amid collapsing oil prices; oil is the kingdom's primary source of wealth.
Mohammed took to his duties with vigor. He enacted
austerity measures to stanch fiscal bleeding, and when Iran-backed Houthi rebels captured the Yemeni capital, MBS went to war in what became one of several proxy conflicts in which Riyadh and Tehran stand on opposing sides.
The prince then unveiled an ambitious social and economic reform program
entitled Vision 2030, vowing to diversify the economy by selling part of the state-owned oil company and promoting new businesses to reduce dependence on oil exports. The plan also calls for boosting the presence of women in the workforce and softening Saudi Arabia's hard-line social rules. "Our vision," he said
in the plan's foreword, "is a tolerant country, with Islam as its constitution and moderation as its method."
Until now, Saudis who object to the break with the traditional succession rules and to MBS's social and economic changes have kept their misgivings at a whisper. The latest announcement was accompanied by news
that religious scholars and the council of princes approved of the new crown prince.
National television showed the now-former crown prince, Mohammed bin Nayef, also stripped of his job as interior minister, pledging allegiance
to MBS. But the new crown prince, who has won this round in the Saudi "Game of Thrones," will have to keep a close eye on his critics.
Social changes are already taking place, and the country's young people especially, sound excited about prospects for more. Vision 2030 acknowledges discontent with rules that block access to most forms of entertainment. "We are well aware," it says
, promising major changes, "that the cultural and entertainment opportunities currently available do not reflect the rising aspirations of our citizens and residents."
Many changes have already gone into effect, some concerning the status of women. Saudi women still face more restrictions than women practically anywhere on Earth. The main obstacle
is the guardianship system, which treats women as children, requiring them to have authorization for activities that in most countries any adult can undertake. Those restrictions were
recently loosened, but the system remains in effect.
Saudi women remain
banned from driving. MBS said last year that
"we believe women have rights in Islam that they've yet to obtain," but said he's "not convinced" that the time is right to lift driving restrictions because of social resistance.
If he is moving cautiously on female emancipation, he doesn't appear risk-averse on foreign policy. The war in Yemen continues with no end in sight, despite sharpening criticism from human rights groups.
And there are signs
that acrimonious relations with Iran will only get worse. In a widely-broadcast television interview last month, he said dialogue with Iran would be pointless, explaining that the Shiite regime in Iran seeks to take control of the Islamic world, with Saudi Arabia as a "primary target." He added ominously,
"We won't wait for the battle to be in Saudi Arabia. Instead, we'll work so that the battle is for them in Iran."
He is currently leading, along with close ally the United Arab Emirates, a diplomatic offensive against neighboring Qatar -- which has ties with Riyadh and Tehran and with Muslim Brotherhood-linked groups. Prince Mohammed appears to be trying to move beyond the traditional Saudi defense strategy of relying on the United States for protection, deploying a muscular military and diplomatic policy.
Still, he views the United States and Donald Trump's administration as a most crucial ally. He visited the American President in Washington in March, laying the groundwork
for Saudi Arabia to become Trump's first foreign stop as President. Despite some confusion
about Trump's foreign policy, the ties between Washington and Riyadh look as strong as ever.
Prince Mohammed has secured a major personal victory by moving just one step away from the throne. But he faces enormous challenges. Oil prices remain depressed, squeezing the Saudi economy. If his multipronged plans succeeds, he will have become a historic, transformational figure. If they fail, the consequences could shake the Middle East and the rest of the world.
In this game of thrones, change is coming either way.