US President Barack Obama’s visit to the Kingdom of Saudi Arabia comes at a crucial moment for one of the Middle East’s most enduring strategic alliances.

The US has long been the backbone of Saudi Arabian security, investing heavily in supplies and training for its army, air force, National Guard and Interior Ministry. This is not to say that the relationship is one of suzerainty: there have been mutual benefits to both sides, and since the 1973 oil shocks following the Yom Kippur War the Saudis have flexed their muscles intermittently to remind Washington that it is not a unidirectional relationship.

However, the relationship has come under tremendous strain in recent years. Cracks first began opening in 2011 following the fall of Egyptian President Hosni Mubarak, a stalwart ally of Riyadh, whom the Americans did nothing to prevent from falling. American passivity in the face of instability in Bahrain, its reluctance to take military action against Syrian President Bashar Al-Assad, and the US’s never-ending failure to stop Israeli settlement construction on Palestinian land have all prompted reams of criticism from Riyadh. Saudi commentators now openly talk of the Kingdom “going its own way,” defining its policy priorities as it sees fit and giving less thought to the concerns of Washington.

Feeling slighted, the Saudis will expect Obama to make a significant commitment to them on a number of issues, most important of which is the current US engagement with Iran. It is no secret that the Saudis are extremely unhappy with the interim agreement currently in place, in which Iran gains some 7 billion dollars of sanctions relief for doing nothing but slowing down its nuclear enrichment program. The problem was compounded by the discovery that Washington had been holding secret communications it held with Iranian negotiators in the Sultanate of Oman without the knowledge of either Israel and Saudi Arabia, after having told both countries it was doing no such thing.

The problem here is one of perception. The Saudis do not oppose a diplomatic pathway to an agreement on the issue of Iran’s nuclear enrichment program, but they do oppose the temptation for Western policymakers to build a Chinese wall between the nuclear issue and the problems of Iran’s status across the region. In an interview with the US’s National Public Radio, Robert Malley, the Obama administration’s chief thinker on Gulf engagement, asked: “Do we have a stake—or should we have a stake—in the broader Sunni–Shi’ite confrontation? Should we take sides in this religious war?”

The truth is that Washington is fast losing interest in macro-conflicts it has no chance of influencing. But the US’s current approach, dealing with the nuclear issue in isolation from larger questions of Iran’s power and esoteric notions of Sunni–Shia and Arab–Persian rivalries that underpin competition with Saudi Arabia, is unlikely to find many supporters in Riyadh.

The time for America to show its support is now. But in order for the Saudis to be placated, the US has to take a side in the regional cold war with Iran, which it is adamant it will not do, especially while nuclear negotiations are ongoing.

While US policy makers may see nuance and shades of grey in complex questions of regional stability, this is not the way it looks in Riyadh. Iranian influence, as they perceive it, grows directly at the expense of their own; Lebanon, Gaza, Syria, Iraq, Kuwait, Bahrain and Yemen are all countries in which the Saudis perceive Iran to be extending its influence and trying to turn the regional strategic equation in their favor.

Then there is the upstart Qatar, the country comprising just “300 people and a television station” that seems to have caused the Saudis no end of irritation, with its support for the Muslim Brotherhood and vehement opposition to the new regime in Egypt. The current diplomatic spat, which has led to the withdrawal of Saudi Arabia’s ambassador (alongside the ambassadors from Bahrain and the United Arab Emirates), has led to an escalation of rhetoric between the Kingdom and the Qataris that threatens to create severe intra-GCC tension.

While this problem has not escalated into full-on confrontation, it should give Obama and his team pause for thought. US CENTCOM is headquartered at the Al-Udeid airbase just to the southwest of Doha, the Qatari capital. The Americans will once more be under pressure to pick a side—again, something they cannot do.

The challenge for Obama is going to be how the US can communicate that it does not share Riyadh’s vision for the region, and cannot take the positions the Saudi government desires, whilst simultaneously ensuring that its security relationship and guarantees to the Kingdom remain robust. It is unlikely that Obama will successfully achieve this.

Policy wonks in DC may feel that it is enough of a signal of friendship that Obama is making the trip to Riyadh, given that his only other visits to the region were to Egypt in 2009 and Israel in 2013. But for the Saudi government, this is the bare minimum needed to move the relationship back to a more positive footing. In the eyes of the Saudis, America has let them down on almost every issue of regional security. The visit is not optional.

It is somewhat uncertain how the relationship will progress, and both sides may have to accept that their relationship will no longer be characterized by the friendship that once existed. Instead, hard calculations of realpolitik will be the driver behind the ties that bind.

This article was originally published in The Majalla.

All views expressed in this blog post are those of the author and do not necessarily represent the views of, and should not be attributed to, The Majalla magazine or Asharq Al-Awsat newspaper.