Barely three months on the throne, Saudi Arabia's King Salman bin Abdulaziz has rearranged the kingdom's line of succession – bumping his half-brother, Prince Muqrin, from his place as crown prince and replacing him with the King's nephew, Mohammed bin Nayef, the kingdom's powerful Interior Minister.
By that one move, King Salman shows his determination to pursue a highly aggressive foreign policy and restores the royal lineage of the so-called Sudairi Seven – the seven sons of Ibn Saud delivered by his favoured wife.
The changes come as the world's largest oil exporter faces unusually low oil prices, a rising tide of Islamic extremism and a full-fledged war in neighbouring Yemen.
The King's son, Prince Mohammed bin Salman, 34, was also elevated Wednesday to second-in-line to the throne – a surprising leap for a man so young and inexperienced. Appointed as Defence Minister only in January, Prince Mohammed bin Salman has been leading the charge against Iranian-linked rebels in Yemen.
Together with Crown Prince Mohammed bin Nayef, 55, who is best known for his relentless crackdown on al-Qaeda inside the kingdom a decade ago, the two Prince Mohammeds are a formidable if heavy-handed duo, said Bruce Riedel, a specialist on Saudi Arabia at the Brookings Institution in Washington.
Together with King Salman, they are pursuing "the most assertive foreign policy in recent Saudi history," he wrote Wednesday.
Crown Prince Mohammed bin Nayef is the son of the late crown prince Nayef bin Abdulaziz, who served as interior minister from 1975 to 2012. Crown prince Nayef, who, like King Salman, was one of the Sudairi brothers, was so fearsome in cracking down on dissidents he was nicknamed the Black Prince.
Preparing to fill his father's shoes, his hard-working son went to school in Oregon and trained with the U.S. Federal Bureau of Investigation and Scotland Yard before joining the Saudi Interior Ministry.
In 2009, Crown Prince Mohammed bin Nayef, then a deputy to his father, was lightly wounded when a militant, who came to see him, detonated a bomb hidden in his intestines.
Not surprising, perhaps, he appears to share his father's contempt for Islamic militants. Last year, he urged Arab countries to join together in eradicating the Muslim Brotherhood, even though several of the countries have long-standing and good relations with the Brotherhood.
Should he succeed King Salman, the Crown Prince will be the first monarch drawn from the third generation of the House of Saud. His grandfather, King Abdulaziz, or Ibn Saud, established the kingdom in 1932 and ruled it until his death in 1953.
Crown Prince Mohammed bin Nayef and his wife have only two daughters, so he is said to have no direct interest in who would succeed him. Observers, however, might say he views Prince Mohammed bin Salman as the son he never had.
The Defence Minister, who was unknown to most Saudis just four months ago, has become "the face of the Yemen war," Mr. Riedel said – "constantly on Saudi TV appearing to direct the war effort and meeting with foreign leaders to win support for the campaign against the pro-Iranian Zaydi Shia Houthi rebels."
"He is considered ruthlessly ambitious and is very close to his father," he added.
According to a statement from the royal palace, the outgoing Prince Muqrin, 69, asked to be replaced as crown prince. Mr. Riedel doesn't believe it.
"No crown prince has ever given up the position in the history of the modern kingdom," he said. "When Salman ascended the throne in January, the press trumpeted Muqrin as heir and there was no sign he was not eager to be the next in line."
More likely, he was asked to step aside, he said.
"He is not close to Salman's branch of the family, the Sudairis," Mr. Riedel said, by way of explanation.
"He also appeared less enthusiastic about Salman's war in Yemen," he added. "As a former fighter pilot, Muqrin understands the limits of air power and he may have had doubts about the wisdom of what was initially called Operation Decisive Storm, but has now become a stalemate."
Saudi watchers agree that the new lineup of King Salman and the two Mohammeds are very much pro-American but are riven with doubts about U.S. reliability. They think that U.S. missteps in Iraq left that country dominated by Iran and that U.S. President Barack Obama is overeager for a rapprochement with Tehran.
"The Yemen war," said Mr. Riedel, "is part Saudi-Iranian regional rivalry, part the unfinished business of the Arab Spring revolutions and part sectarian Sunni-Shia animosity."
"It is, above all, the Salmans' war, father and son together," he said. From their view, "Iran already dominates decision-making in Baghdad, Damascus and Beirut" and they do "not want a fourth Arab capital to be aligned with Tehran.
"The surprise elevation of [Crown Prince Mohammed bin Nayef] and [Prince Mohammed bin Salman] underscores how the stakes in this war are crucial, not only to Yemen's future but increasingly to the future of the House of Saud."
The woman behind the Saudi throne
Saudi King Salman wasted little time in making a dramatic change to the line of succession in the House of Saud, and it may all be because of his grandmother, a reportedly beautiful and influential woman named Hassa bint Ahmad al-Sudairi.
Born in 1900, Ms. al-Sudairi is reported to have married Abdulaziz bin Saud (or Ibn Saud), the future founder of the kingdom of Saudi Arabia, twice – the first time in 1913 when she was a very young woman. Their marriage was apparently part of unifying tribes in the central Nejd district of the Arabian Peninsula. After subsequently marrying Abdulaziz's half-brother, Ms. al-Sudairi returned to Abdulaziz in 1920, and the couple remained married until Ibn Saud's death in 1953.
Though the king had some 21 other wives and concubines, it was said that Ms. al-Sudairi was his favourite, partly because she bore him more sons (seven) than did any other wife, along with four daughters.
Altogether, Ibn Saud had close to 100 children, 45 of them sons. In the competitive world of Saudi royalty, the seven brothers born to Ms. al-Sudairi formed an alliance that would later ensure their continued prominence.
King Fahd (1982-2005) was the couple's oldest son; Prince Sultan was crown prince (2005-2011); Prince Nayef was minister of the interior (1975-2012), and Salman is the new king. The other three brothers have served in lesser but important positions.
The exception to Sudairi rule was the late King Abdullah, who succeeded Fahd in 2005. He had been named second-in-line to the throne by a previous non-Sudairi, King Khalid (1975-82) and became crown prince when Fahd became king in 1982. Abdullah remained in position to ascend the throne by combining the support of many other descendants of King Abdulaziz who were passed over in favour of Sudairis for various positions.
Once a Sudairi, King Salman, was back on the throne, however, he quickly made sure his successor would come from the Sudairi line.