(Bloomberg Opinion) -- In the summer of 2018, arguing that death was the surest agent of change in the Middle East, I included Oman’s Sultan Qaboos bin Said in the list of four leaders whose passing would shake up the region. The three others were King Salman bin Abdulaziz of Saudi Arabia, Supreme Leader Ali Khamenei of Iran and Grand Ayatollah Ali Sistani of Iraq.

Noting Oman’s unusual succession mechanism — Qaboos would nominate an heir in a sealed letter, to be opened upon his death, but only if his extended family couldn’t arrive at a consensus among themselves — I predicted that “a process so peculiar can hardly be expected to proceed smoothly.”

I was dead wrong. After Qaboos’s passing last week, the succession proceeded smoothly and swiftly. The family decided not even to try for a consensus: Instead, the envelope was unsealed, and the late sultan’s choice, his cousin Haitham bin Tariq, enthroned.

Whether this decision represents a shirking of responsibility by the family or a voluntary renunciation of privilege, the reasoning behind it is simple. The grandees, aware that Oman faces a perfect storm of economic and geopolitical upheavals, felt they could ill afford a potentially divisive debate over the succession. It was imperative to preserve the consensus that Qaboos had built over five decades.

Haitham’s reign begins with both the blessing and the curse of Qaboos. Since he was the late sultan’s choice, no Omani royalist can question his right to rule, a good position from which to begin negotiating that perfect storm.

But the new ruler will find that political legitimacy is subject to the law of diminishing returns: From here on, he will be judged by his performance. To make matters even more difficult, Haitham’s performance will be measured against the very high bar set by his predecessor.

Under Qaboos, Oman had five decades of political stability, which is rare enough for the region. More impressive still, it enjoyed an astonishing streak of economic growth. It is the only Middle Eastern country, and one of only 13 anywhere in the world in the postwar period, to have grown at 7% annually for 25 years.

These achievements, combined with Qaboos’s innate skills as a diplomat, allowed Oman to become the go-between of choice for squabbles in a very contentious neighborhood, even for the confrontation between a superpower and a regional one. There is a straight line from Qaboos’s mediation between the U.S. and Iran to the 2015 nuclear deal.

Although Haitham has vowed to maintain his country’s position as a regional peacemaker, he may not be expected to play Qaboos’s role in the current confrontation between the Trump administration and the Islamic Republic. At the moment, it is not clear that the two parties want an honest broker. If they did, there are other candidates, ranging from Kuwait’s ailing Sheikh Sabah Al-Ahmad Al-Jaber Al-Sabah to Japanese Prime Minister Shinzo Abe.

This should be a relief for the new sultan, enabling him to concentrate on Omani matters. These are twofold: economic difficulties at home, and tensions with the neighboring United Arab Emirates.

The hot growth streak is now a receding memory: Recent years have been difficult. A Bloomberg survey of economists suggests Oman’s economy will expand by 1.5% in 2019 and 2.8% in 2020. Its finances hobbled by low oil prices, the country plans to borrow $5.2 billion to plug a hole in its 2020 budget.

Relations with the UAE have been strained. Muscat has periodically accused Abu Dhabi of espionage and attempts to undermine the sultanate. The UAE and Saudi Arabia were unhappy about Oman’s decision to stay out of their quarrel with Qatar, and are suspicious of its ties to Iran and, more recently, to Israel.

Qaboos’s stature meant no other ruler in the Gulf Cooperation Council openly questioned his motives. Now, as the new kid on the block, Haitham will undoubtedly come under greater pressure. Having conferred on him the blessings of Qaboos, his family — and his country — can only hope that he escapes the accompanying curse.

To contact the author of this story: Bobby Ghosh at aghosh73@bloomberg.net

To contact the editor responsible for this story: James Gibney at jgibney5@bloomberg.net

This column does not necessarily reflect the opinion of Bloomberg LP and its owners.

Bobby Ghosh is a columnist and member of the Bloomberg Opinion editorial board. He writes on foreign affairs, with a special focus on the Middle East and the wider Islamic world.

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