Barack Obama has arrived in Saudi Arabia to face some potentially awkward questions from his hosts – not least over a push by some of his political allies for the kingdom to be held responsible in US courts for any role in the 9/11 terrorist attacks.

The US president landed in Riyadh on Wednesday on his final trip to the region before leaving office. He will try to smooth the ruffled feathers of Saudis, Emiratis and Bahrainis who have come to resent their longstanding ally for “tilting” towards their rival Iran and pressing too hard for domestic reforms they fear will undermine the autocratic status quo.

Adding to Obama’s diplomatic headache is legislation proposed by Senate Democrats that would enable victims of the 9/11 attacks in New York and Washington to sue the Saudi government if it is found to have been involved. Fifteen of the 19 airline hijackers were Saudi citizens but the government has long denied any connection.



Former secretary of state Hillary Clinton and Senator Bernie Sanders, each seeking the Democratic presidential nomination, both said they back the measure, but Obama has spoken out against it. Saudi Arabia has reportedly warned the White House that if the bill is enacted, it might retaliate by selling up to $750bn (£520bn) in treasury securities and other assets in the US.

“If that legislation passes without being watered down, it will pose a very serious problem for the relationship,” said Bruce Riedel, a veteran of the CIA for 30 years and now an intelligence analyst at the Brookings Institution thinktank in Washington. “If members of the Saudi government are taken to court, there will be retaliation from the kingdom.”

The move comes amid a renewed push to declassify a 28-page section of a 2004 US government report on the 9/11 attacks that is believed to detail possible Saudi links to the plot. Riedel added: “The simplest solution to the problem is for the administration to declassify that 28 pages, which is what the Saudis want us to do, and then let everyone see if there’s a smoking gun in there.”

But despite the negative headlines, Riedel noted that the US, UK and Canada have all struck the biggest arms deals in their histories with Saudi Arabia in the last few years. “One has to separate rhetoric and reality in this relationship,” he said. “There is an unprecedented degree of criticism of Saudi Arabia in the United States, even from the president. On the other hand the security, military and intelligence relationships are probably stronger than they’ve ever been before.”

Publicly, of course, it will be all smiles and carefully staged photo opportunities at Thursday’s regional summit: at least this time King Salman of Saudi Arabia will actually be there, having conspicuously stayed at home last year when the other Gulf Cooperation Council leaders trooped to Camp David in the nervous run-up to the landmark nuclear agreement with Tehran.

But following a recent interview in Atlantic magazine, in which Obama referred to some Gulf countries as “free riders” because of their overreliance on US military action, there is no mistaking the undercurrent of hostility. “The goals of Obama’s visit are incomprehensible,” commented the Saudi journalist Hussein Shobokshi , adding that it should at least put an end to a turbulent period in relations.

“The president will deliver a message of reassurance to mitigate some of the fallout we’ve seen,” predicted Frederic Wehrey of the Carnegie Endowment for International Peace. Rob Malley, Obama’s top Middle East adviser, has highlighted “much greater cooperation” with the GCC. Agreements on defence, counter-terrorism and cyberwarfare will accentuate the positive.

Ashton Carter, the US defence secretary, who is accompanying the president, said he expects GCC financial help in stabilising Iraq as well as an enhanced effort to fight the jihadis of the Islamic State. Plummeting oil prices, production quotas and far-reaching Saudi economic reform plans are certain to figure in talks between the king and the president.

Accumulated US-Saudi irritations go back over a decade to the overthrow of Saddam Hussein under George Bush, the rise of Iraq’s Shias and the abandonment of Hosni Mubarak of Egypt in the early days of the Arab spring. Obama’s vacillation on Syria, in Saudi eyes empowering Bashar al-Assad’s Iranian ally, angered King Abdullah.

But under the more assertive King Salman and his ambitious son, the deputy crown prince Mohammed Bin Salman, tempers have frayed even more, especially over Iran, the Saudi-led war in Yemen – despite US support - the rise of al-Qaida there, and what are seen in Washington as the kingdom’s half-hearted efforts against Isis.

Saudi statements about deploying troops and aircraft to Syria and Iraq have been more about PR than real deployments, while the creation of an Islamic anti-terrorist alliance has a Sunni sectarian feel to it and seems mainly designed to challenge Tehran and its Shia proxies in Lebanon, Syria and the Gulf. Saudis often admit that they feel more hostile to Iran than to Assad.

After the Atlantic interview, Prince Turki al-Faisal, the former Saudi intelligence chief, retorted that Obama was being “petulant” and “adding insult to injury” in equating “the kingdom’s 80 years of constant friendship with America” with an irresponsible Iran.

Saudis counter that the answer to Obama’s criticism is the “Salman doctrine” – a demonstration that they are now willing to lead, as in Yemen, and take initiatives, but still demanding that the US remains a loyal ally that provides logistical and intelligence support when needed. The results so far, though, are patchy to say the least.

If mutual annoyance is unmistakable, reports of the death of the relationship between Riyadh and Washington are premature. “We may get angry and reproach one another,” wrote the commentator Jamal Khashoggi, “but we cannot do without each other.” Another prominent Saudi intellectual quipped that the only thing worse than Obama would be having Donald Trump in the White House.

“For years we’ve been telling the Americans, ‘OK you don’t want to remove Assad but at least set up a no-fly zone because his barrel bombs are producing radicalisation,” said one analyst. “And then Obama drew the ‘red line’ over chemical weapons and backed down when Assad used them. Obama doesn’t have a doctrine, let alone a policy. Yes, the Saudi-US relationship has been damaged but it has survived. And it isn’t just about summits and meetings. It’s institutional: there is still defence cooperation and intelligence sharing on a massive scale.”

Carnegie’s Perry Cammack said: “The end of the Obama administration can’t come quickly enough for some of these leaders. But the real question is what comes with the next administration. And their hope of course is that, with a new presidency, things will revert back to, to how they’ve been for decades. I’m not so sure that’s the case. There have been some deeper structural changes in the relationship which we’ll have to wait and see what those look like over the next couple of years.”