THE airstrikes undertaken by a Saudi-led coalition against targets in Yemen may usher a new phase in one of the longest, most destructive, and most confused conflicts to affect the Middle East and much of the Muslim world: the Saudi-Iranian confrontation.

Long before the US intervention in Iraq in 2003, the Arab Spring in 2011, and the ensuing chaos that threatens regional and international orders, the Middle East had witnessed considerable geo-strategic shifts. The 1979 Islamic revolution in Iran may have been the most saliently disruptive such event. It toppled a Western ally, introduced Islamism as a viable political force, and, through Tehran's new bellicose rhetoric and military reach, threatened global economic stability. The new Islamic Republic was however contained by both regional and international actors — through a devastating eight-year war with Iraq, and a sanctions regimen that continues until today. Iran did succeed nonetheless in gaining inroads into the political order of the region through its sponsorship and eventual leadership of the "resistance axis" — state and non-state actors opposed to Israel and the West and committed to a radical resolution of the region's woes, one that openly calls in particular for the eradication of Israel as a colonial outpost. With a pro-Western Iran now part of the past, Saudi Arabia, on the other hand, assumed the paramount in the "moderation axis", the informal alliance of regional actors espousing a less confrontational pursuit of regional and international accord, one that is responsive to Western economic needs and implicitly accepts Israel as a de facto reality to be accommodated.

The confrontation between Iran and Saudi Arabia can thus be summarized as an opposition between two approaches, radical and moderate, towards the problems of the Middle East. The ideological and policy differences, however, seem to have faded in what increasingly appears to be a generic competition for influence and hegemony, only to be replaced, in media polemics, with accusations of Sunni versus Shi'i sectarianism.

Much indulgence has recently been expanded in portraying Saudi-Iranian confrontation in essentialised sectarian terms. For detractors of Iran addressing audiences with Sunni sensibilities, the origin of the enmity is Tehran's aggressive sectarianism, as demonstrated by the ritualized festive celebration of the assassination of Caliph Umar, and the public cursing of the Prophet's wife Aisha. Iran, according to these detractors, is engaged in a stealth religious war against the Sunni world, infiltrating and converting Sunni communities, under the false banner of Muslim unity. The mirror image of these accusations is directed at Saudi Arabia. For its detractors, it is the Saudi religious establishment that is committed to the destruction of the pluralism and diversity of Sunni Islam, imposing itself on communities worldwide, destroying their spiritual heritage, and forcing the application its own austere version of the faith — while condoning and supporting, even if indirectly, violent attacks on Shi'i minorities.

These accusations are faced with official denial and rebuke, in each of Tehran and Riyadh. Both Iran and Saudi Arabia have declared themselves committed to Islamic unity and moderation, against sectarianism and intolerance. Both, however, have often been less then charitable with their respective religious minorities. Sunni Iranians are denied the right of congregation in Tehran, while Shi'ite Saudis have to endure the litany of pronouncements by the religious establishment denigrating their practices.

Still, the claims, on the part of the respective political leadership, of efforts at combating discrimination and reigning in on clerics and scholars with a sectarian bent cannot be dismissed as insincere. It is in the fundamental interest of both Saudi Arabia and Iran to contain the volatility and violence that are generated by inflammatory sectarianism. It is, however, also in their distinct advantage to maintain a manageable level of sectarian mobilization, to summon political support domestically, and to realise options for action in their regional conflict.

In each of Syria, Iraq, Lebanon, Yemen, and Bahrain — countries in the Middle East enduring severe levels of internal strife, Saudi Arabia and Iran provide support for opposing sides. The conflicts in these countries may not have originated with the diverging policies of Riyadh and Tehran. They have, however, been transformed into proxy confrontations between the two regional powers.

Both Iran and Saudi Arabia have instrumentalised sectarian impulses in areas of confrontation. The Iranian Revolutionary Guards Corps (IRGC) oversees the recruitment and deployment of international Shi'i militias in its support of the Damascus dictatorship against the Syrian uprising, while Saudi Arabia has staunchly resisted the emergence of a (Shi'i-majority) constitutional monarchy in neighbouring Bahrain. In Iraq, Saudi distrust of the Tehran-leaning leadership of the Shi'i majority has contributed to the alienation of Baghdad from its Arab environment, leaving it, counter-productively, with little recourse other than Iran. Across the Middle East, Saudi and Iranian funds, resources, and intelligence services, as well as loosely funded media organizations engaged in political and sectarian rhetoric, have been locked in a high stake competition that has required successive escalations.

With the looming framework agreement between Iran and the US-led P5+1 group, presumably on nuclear restrictions and lifting of economic sanctions, Saudi Arabia's confidence in a US alignment in its favour was eroding. But it was in Yemen, in the Arabian Peninsula itself, that Iran crossed a "red-line", from the Saudi perspective.

With the coup staged in Yemen by its allies, and hints of far-reaching implications for the agreement with the P5+1, Tehran seemed boastful of an imminent victory at the regional scale. The prospect of Iran prevailing is in fact illusory: even if successful in eliminating Saudi influence, Tehran would have to contend with a fierce Sunni radicalism — informed by its own experimentations with Islamism, and would not be able to pacify the region. The feared outcome of allowing Iran to ravel in the illusion of victory, from a Saudi perspective, is the empowering of such Sunni radicalism, at the detriment of order and control in Saudi Arabia itself, as well as in adjacent territories.

The Saudi-led operation in Yemen is thus both the Saudi response to excesses on the part of Iran in the low-intensity confrontation that opposes the two regional powers, and a pre-emptive strike against an outburst of Sunni radicalism, enhanced in reaction to Iranian hubris. The war in Yemen, however, is a high stakes gamble: were it to succeed and reverse the effect of the pro-Iranian coup, it would have dealt a severe blow to Iranian gravitas, and would require from Tehran in response another high profile regional action. Were it to fail, it would embolden both Iran to pursue more adventures and Sunni jihadism, now cast as the last best hope against Shi'i expansionism.

In Yemen, Riyadh and Tehran are thus engaged in a dangerous exercise with no foreseeable positive outcome, unless the two capitals revert to a real dialogue to address all the dossiers of their enmity. Left to its own dynamics, the confrontation in Yemen will not only lead Saudi Arabia and Iran to open warfare, but will insure that the real victor at the end is radicalism. This is a fact that the leaderships at both sides of the Persian Gulf understand well, but have been willing to ignore in expectation of concessions from the other side.

The irony is that this most dangerous relationship in the Middle East, between Saudi Arabia and Iran, is also the most promising. With no objective grounds for fundamental discord on most issues, Riyadh and Tehran, acting in unison, could usher an era of stability and progress in the region. Were their enmity to be transformed to entente, the sought-after peace and unity may become a realistic prospect. The pre-requisites for such course are wisdom and vision. In Yemen and across the Middle East, Saudi Arabia and Iran are being thus tested.

The writer is Principal, Middle East Alternatives, Washington DC. (Exclusive to The Daily Star.)