The Arab intervention in Yemen shows that pushing back Iran's growing power is the top strategic priority for Saudi Arabia.
On the night of 25th March, Saudi Arabia launched Operation Decisive Storm in neighbouring Yemen. Saudi jets bombed positions held by Houthi rebels who had seized the Yemeni capital Sanaa, overthrown President Abd Rabbo Mansour Hadi and were moving on Aden.
Ten countries are participating in the Saudi-led coalition: the member states of the Gulf Cooperation Council (GCC) minus Oman (Saudi Arabia, the United Arab Emirates, Kuwait and Qatar) plus Egypt, Morocco, Jordan, Sudan and Pakistan.
The intervention in Yemen is a response to Saudi concerns about Iran's growing reach. As Tehran negotiates over its nuclear programme, the deal that has been struck will have major implications for relations in the region.
The coalition fighting in Yemen has garnered the support of the United States. The spokesperson for the National Security Council declared that President Obama had authorised the provision of logistical and intelligence support to GCC-led military operations. Washington set up a joint planning cell with Saudi Arabia.
But Jamal Khashoghi, a Saudi journalist with close links to the government, has suggested that Riyadh presented Washington with something of a fait accompli. Faced with what it views as a an expansionist Iranian policy on the one hand and US silence on the other, "it would seem that the Saudi Monarch has decided that Saudi interest comes first and that if Saudi Arabia is forced to act alone so be it," he wrote on 28 March.
The stakes in this war clearly go beyond Yemen - Alain Gresh
If confirmed, this would mark a significant shift in Saudi policy, which has hitherto been highly dependent on the United States.
Pakistan, whilst reiterating its determination to preserve security and the territorial integrity of the Wahhabi kingdom, has expressed some reservations.
"We will not take part in any conflict that could result in differences in the Muslim world, causing fault-lines present in Pakistan to be disturbed, the consequences of which will have to be borne by Pakistan," Defence Minister Khawaja Asif told the National Assembly, in an allusion to persistent tensions between the Shia minority and the Sunni majority.
This reference to denominational differences supports the narrative of a clash between Sunni and Shia Islam, a discord that reaches back to the origins of Islam itself, to the wars of succession after the death of the Prophet Mohammed in 632. Such arguments are backed up by abstract and historically misguided cliches - a thousand-year conflict, ancient hatred, and theological quarrels - which are used to explain events, to the detriment of political and geopolitical analyses.
The difficulty in going beyond a denominational reading in order to reveal the power struggles that actually govern the region's conflicts stems from the fact that the actors on the ground themselves give credit to the sectarian reading of the conflict and act accordingly. This leads to a simplification of the situation in the minds of analysts and fighters alike.
The Houthis, we are told, are Shias and their progression is antagonizing their powerful Saudi neighbour. Yet in September 1962, when a republican coup finally ended the thousand-year rule of the Zaydi Imamate in Sanaa, a long civil war ensued in which Riyadh supported, financed and armed the Zaydi tribes. The Zaydis are a branch of Islam attached to the Shia Islam, but unlike Iranian Shias, they only recognize five Imams, not 12. For many years seen as "moderates" - they often pray side by side with Sunnis in their mosques - over recent years they have been subject to the influence of Tehran. As indicated by Simon Henderson, an analyst belonging to an American think tank dependent on the powerful pro-Israel lobby, and unlikely to sympathise with the Mullahs: "We do not know the extent of Iran's support for the Houthis - and we do not know if the Iranians consider their coming to power as a strategic goal or a fortuitous consequence of events."
A declaration made by an Iranian official last year, affirming that three Arab capitals - Damascus, Baghdad and Beirut - were already under Iranian control was not enough to prove the presence of an Iranian grand design. Indeed, in the 2000s during the presidencies of Hashemi Rafsandjani (1989-1997) and Mohammad Khatami, (1997-2005), ties between Tehran and Riyadh grew stronger.
Yemen cannot be reduced to a simple chart of denominational analysis. Firstly, it is one of the four countries where the "Arab Spring" led to the departure of the president, after a long fight characterized by armed clashes, but also by the active youth movement which has not abandoned its role, despite weakening due to the militarization of encounters between elites. At least four forces occupy the terrain shaped by a set of unstable alliances:
Former President Ali Abdallah Saleh, to whom a large proportion of the army remains loyal. He is also Zaydi, but spent years fighting the Houthis, with the support of Sunni Islamists, before allying himself with the Zaydi group in the hope of regaining his power. Their alliance appears fragile and the General People's Congress of the former president criticized the Houthi offensive in the south.
The Southern Movement, which lamented the loss of southern independence with the demise of the People's Democratic Republic of Yemen (PDRY), South Yemen. Since the unification of the two Yemens in 1990, they have rebelled several times against the centralized authority and are once more rallying for independence. Allied out of convenience at present with Hadi and the Muslim Brotherhood-influenced al-Islah party in their fight against the Houthis, they will not easily forget that it was these two groups who led a violent repression against them, particularly in 1994.
Al-Qaida in the Arabian Peninsula (AQAP). It of course opposes the Houthis, but has no sympathy whatsoever for President Saleh, nor for Saudi Arabia, against which it has carried out clandestine attacks.
Finally, Islamic State announced its appearance on the scene in Yemen on 20 March, with an attack in a Sanaa mosque killing roughly 150 people.
Riyadh's involvement The stakes involved in this war clearly go beyond Yemen, which is but one of many fronts in a region mired in chaos and complex fighting between foreign powers, dictatorial regimes clinging to power and non-State militia groups.
One question might examine the reasoning behind Saudi involvement. Riyadh plans to make available around one hundred fighter planes and is said to have gathered 150,000 soldiers on the border with Yemen. Is this a question of demonstrating, in the face of Iran, and with a partial withdrawal from the United States, that the country wishes to recover a central role across the region? Does this mobilization signal a political reorientation driven by the new King Salman and the young princes in his entourage?
Nawaf Obeid, a Saudi intellectual close to those in power, believes so.
"The new Saudi leadership - centred on a cadre of youthful, dynamic royals and technocrats - is developing a foreign policy doctrine to address long-standing regional tensions," he wrote in the Washington Post. "This doctrine is based on the legitimacy of the Saudi monarchy and the centrality of the kingdom to the Muslim world. As the custodian of the holy mosques of Mecca and Medina, Saudi Arabia is uniquely positioned to rise above the fray of the past decade and begin bridging the considerable gaps dividing the main Sunni nations."
But does the Saudi army have the means necessary for this strategy? It already suffered one defeat by the Houthi militias in 2009, who despite insufficient weapons were in control of their territory. Can Saudi Arabia commit ground troops, at the risk of locking its soldiers into a stalemate just as Egypt did during its intervention in Yemen between 1962 and 1967? Several Egyptian commentators are questioning the duration of such an intervention and its political objectives.
If there has been something of a reshuffle in the region, the so-called "Sunni" alliance is not without its rifts. The "Persian menace" is not enough to paper over all the cracks. Saudi Arabia has seemed a little more conciliatory towards the Muslim Brotherhood than in 2014, forging closer links with Qatar and Turkey, whilst the latter is regularly denounced by Cairo.
Even Sunni Islamist organisations appear somewhat reserved concerning an intervention that divides the Muslim world. The Egyptian Salafi Front whose figurehead is the charismatic Sheikh Abu Ismail (currently in prison), sees the fighting in the region as "a clash between the West and Islam", in which "Arab regimes which support the American-Zionist cause are looking to defeat the uprisings of the Arab peoples."
What is at stake? The geopolitical importance of Yemen cannot be ignored. The country controls entry into the Red Sea (towards the Suez Canal) and the Bab-el-Mandeb strait, which although less important than the Strait of Hormuz, is the point of passage for oil and gas on its way to Europe.
Stability in Yemen is also a vital strategic goal for Saudi Arabia. The late King Abdulaziz famously told his sons: "What is good for you and what is bad for you comes from Yemen."
Since September 11, Yemen has been a central element in the "fight against terrorism". American special forces were stationed there, coordinating actions against AQAP - in particular drone strikes. Yet the United States has recently evacuated their base in Al-Anad following the advance of the Houthis towards Aden, and the Americans find themselves shoulder to shoulder with AQPA in the fight against the Houthis.
Washington is faced with a similar dilemma in Iraq, where Shiite militias, organised and trained by Tehran, are leading the offensive against IS. In the current offensive with troops from Baghdad fighting the IS-controlled town of Tikrit, the United States provided aerial aid on the condition that the Iranian militias were withdrawn.
On the eve of the conclusion of negotiations over Iran's nuclear programme, Saudi Arabia upped its game. It is asserting its ground in the face of Tehran, and preparing for two scenarios: an agreement and the reintegration of Iran in the regional game by the West; or failure with an array of potential military escalations.