-Op-Ed-

PARIS — In the 1970s, in the aftermath of Richard Nixon's visit to China , commentators talked about the Washington-Moscow-Beijing triangle. These days, in the Middle East, there is another triangle: between Riyadh, Tehran and Washington. The problem for the region's stability is that this triangle is absolutely dysfunctional. Indeed, the only way to understand the dangerous escalation between Saudi Arabia and Iran is to highlight the role — or rather, in this case — the relative timidity of the United States.

While the U.S. is no longer dependent on the Middle East for energy, Saudi Arabia now marches to its own beat. And its autonomy isn't following the right direction, to say the least. Until very recently, Saudi diplomacy combined "a generous checkbook and a low profile." If Riyadh wasn't lurking in the shadows, it was, at least, treading with some degree of prudence. Now it looks like it wants to compensate for its weakening financial resources with boldness and visible initiatives.

By executing Shia cleric Nimr al-Nimr , Saudi Arabia has taken the risk of aggravating its relations with Iran, and beyond, with the entire Shia Islamic world. It did so deliberately, and mostly for political reasons. For Riyadh, the goal is to divert its population's attention at a time when the dizzying (and probably long-lasting) drop in oil and natural gas prices no longer allows the kingdom to buy itself social peace through subsidies, as it did during the beginning of the Arab Spring.

But to play the card of sectarian and religious nationalism to the brink of war — be it an actual war, like in Yemen , or a potential one against Iran — is always a dangerous move for a fragile regime. Could the Saudi regime one day face the same fate as that of France's Second Empire (1870) or of the Austro-Hungarian Empire (1918), which didn't survive military defeat?

Of course, Riyadh's headlong rush can also be explained by personal reasons. To say that the Saudi court lacks a Kissinger is putting it mildly. Prince Saud Al-Faisal, who led the kingdom's diplomacy for 40 years, didn't find a worthy successor. With a political system that's flawed in its principle and weakened in its legitimacy by an ideology and a religious practice that, seen from abroad, don't seem that different from those of ISIS , Saudi Arabia seems to be using its obsession of Shia Iran as its identity's main driving force. For France , which has been banking on Saudi Arabia for several years, its evolution of behavior is cause for concern.

An unrecognizable ally

What real relations can you have with an ally that behaves irresponsibly, on which you no longer have any real influence, and which is both the source of the issues facing the region and a shield against the risk of chaos? If Riyadh no longer listens to Washington, why would it pay any mind to Paris?

Saudi Arabia's responsibility in the current escalation of tensions is resounding. But Iran is far from beyond reproach. In terms of human rights, it is no example. In 2015, Iran executed many more people (about 1,000) than Saudi Arabia. Iranian conservatives saw in the Saudi provocation a convenient excuse to question once again the little progress made by the moderates and President Rouhani since the nuclear deal.

As a matter of fact, ISIS is the only real beneficiary of the escalation initiated by Saudi Arabia and exploited by part of the Iranian regime. It's a paradox. While the terrorist organization is losing ground, it's benefiting from the divisions among its opponents. How can we hope that the process initiated in Vienna for Syria's future will see the slightest progress, if two of its participants are trying to weaken each other instead of ISIS? The same assessment can be made of the conflict in Yemen. If Riyadh and Tehran only talk to each another to insult each other, any compromise in the entire region becomes impossible.

We need to go back to the triangle formula. The United States can't and doesn't want to choose between Saudi Arabia and Iran . But it may be the only country that can still contribute to restoring a form of responsible dialogue between Riyadh and Tehran.

A majority of Iranians support the country's opening to the world, which should in all logic accompany the signing of the nuclear deal. Saudi Arabia felt abandoned — if not betrayed — by an America it understands less and less since the 2003 Iraq war, a conflict that left only one victor: Iran, and by extension the Shia cause .

There is, however, a survival instinct in a large number of Saudi leaders. To denounce U.S. irresponsibility is one thing, but to effectively push Washington into the arms of Tehran is another. America must exert all the means of pressure it has at its disposal to discourage Saudi Arabia and Iran from continuing to flirt dangerously with war.