President Obama, right, meets with King Salman of Saudi Arabia in the Oval Office on Friday. (Evan Vucci/Associated Press)

President Obama’s meeting last Friday with Saudi Arabia’s King Salman came as U.S. officials are anxiously watching a potential succession rivalry between the king’s ambitious young son and the crown prince who is a longtime intelligence partner of the United States.

Salman, 79, was accompanied in his meeting at the White House by his son Mohammed bin Salman, who though just 30 has taken the positions of deputy crown prince, defense minister and chief economic planner. He is officially next in line behind Crown Prince Mohammed bin Nayef, who at 56 has served as head of intelligence and minister of the interior and who has for years been the United States’ key Saudi ally in counterterrorism efforts against al-Qaeda.

Both sides described the White House meeting as successful. Mohammed bin Salman made a personal pitch for a strengthened “strategic partnership” that would feature expanded trade and economic ties beyond the kingdom’s traditional role as an oil exporter. Obama cautioned that the Saudi-led military campaign in Yemen, which Mohammed bin Salman has championed, is creating what one senior administration official described as a “catastrophic” humanitarian situation that “inevitably will spill over into the kingdom.”

U.S. officials have noted in recent weeks the aggressive policy role played by Mohammed bin Salman, and the sense of political jockeying within the kingdom. “MBS,” as he’s known, joined the line of succession as deputy crown prince in April, when Prince Muqrin bin Abdul Aziz was dropped as crown prince and Mohammed bin Nayef, then deputy, moved up into the No. 2 spot. Observers have speculated that if the king changed the succession process once to remove Muqrin, he could do so again to favor his son.

“Let’s face reality,” says one prominent Arab official, when asked about Mohammed bin Salman. “He’s the son of the king. There’s a strong chance he will be the next king. The longer Salman survives, the larger the chance that MBS is next.” This official urges the United States to emulate some Gulf and European countries in cultivating the king’s son as a future monarch.

“Don’t be so worried,” argues this Arab official. “Invest in MBS. Get to know him, like you did MBN [Mohammed bin Nayef]. Take him to Wall Street. Take him to Silicon Valley. Show him you care.”

The counterargument is that the United States should stay out of succession politics in any foreign country, especially in the murky monarchy of Saudi Arabia. Some senior officials believe that anything that’s seen as putting an American thumb on the scale could backfire. Others argue that the risk-reward ratio is high with Mohammed bin Salman; huge potential benefits could come from having a young, dynamic Saudi king who, it’s said, wants to move in the modernizing direction of the United Arab Emirates.

Saudi officials apparently haven’t asked the United States for its views about the succession, but some feel that such a query could come soon — perhaps forcing Washington to decide whether it wants to offer any guidance or remain mum.

King Salman and his son have made some aggressive diplomatic initiatives. They’ve opened a broad dialogue with Russia, sending a large delegation (including several cabinet ministers) to the St. Petersburg International Economic Forum in June. And Saudi Foreign Minister Adel al-Jubeir met his Russian and U.S. counterparts, Sergei Lavrov and John F. Kerry, in early August in Doha, Qatar, for trilateral discussions on Syria.

Mohammed bin Salman’s most intriguing move on Syria was a meeting in Riyadh in late July with Ali Mamlouk, the top intelligence adviser to President Bashar al-Assad. At that meeting, apparently brokered by Russia, the young Saudi defense minister “floated the idea that Assad could stay in power if Iran would go,” according to an administration official. Any such offer to allow Assad’s survival in power would mark a sharp change in official Saudi policy, and a sign of the price Riyadh would pay to reduce Iranian influence in Damascus.

Having invited Russia to assist a Syrian political transition, the Saudis must now reckon with the consequences. Russia began moving military supplies into northern Syria last week, probably to prepare a base from which Russian planes could fly missions against the Islamic State and perhaps other extremist groups that oppose Assad. Russia has also been meeting quietly with some members of the Syrian opposition.

The joint statement issued after Friday’s White House meeting lauded the “enduring relationship” between Riyadh and Washington. That’s true enough, but the United States is certainly puzzling about recent developments inside the opaque Saudi monarchy.

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