Has Iran overreached itself in Yemen?

When the Saudi ambassador in Washington announced the launching of airstrikes and a military intervention in Yemen on Wednesday night, the kingdom surprised everyone - not least Iran.

Conventional wisdom was that Riyadh had dithered and left it too late. The Houthis and elements of the army loyal to the ousted autocrat Ali Abdullah Saleh and his son Ahmed had advanced on the southern city of Aden with such speed that its fall, and that of President Abd Rabbuh Mansour Hadi, was considered only a matter of time.

Saudi Arabia has a long history of military intervention - most of it harmful - in what it considers as its backyard but the region had got so used to Saudi's role as a player of proxy wars in Syria and Iraq that anything as decisive as direct military force seemed to hail from a bygone era.

This time, the Houthis and Iran badly miscalculated. Riyadh's hand was forced for three reasons.

If Aden falls and with it the strategic Bab al-Mandab strait, through which all of the oil traffic of Suez Canal passes, roughly three quarters of the most populated part of Yemen would be in the hands of an Iranian-backed militia, openly threatening Saudi Arabia itself.

Mohamed Bukhaiti, a member of the Houthi Political Council told Al Jazeera on Monday: "I say to Saudi Arabia, it will bear the responsibility of any intervention, and we stress that any intervention will be the end of the Al-Saud regime in the Arabian Peninsula."

Added to that was the crowing that came consistently from Iran itself, which officially continues to deny providing money and training to the Shia Houthi militants, against all evidence to the contrary.

Iranian MP Ali Reza Zakani said: "The Yemeni revolution will not be limited to the Yemenis alone, but will be extended after its success to Saudi territory," saying that "the people of the Eastern Province of Saudi will lead those protests".

He said the events in Yemen were "a natural extension of the Iranian Revolution and 14 out of 20 Yemeni governorates will be under Houthi control soon".

The Iranian website Digraban quoted Saad Al-Din Zarei, a member of the political administration inside the Iranian Revolutionary Guards, as saying that "whispering is getting louder and louder about the presence of the Revolutionary Guards inside the Kingdom of Saudi Arabia." These were direct threats to Riyadh itself.

This brings us to the third factor, which is far and away the most important: could any ruler in Riyadh sit back and watch the leadership of millions of Sunni Arabs collapse in front of a co-ordinated advance of Iranian power - in Iraq, Syria and now Yemen? Could it hand over the protection of Sunnis to al Qaeda and the Islamic State in a tussle for regional control which openly threatened to become sectarian? If the kingdom had sat on its hands, it would have lost legitimacy in the eyes of its own citizens and pushed its youths into the clutches of the Islamic State.

Yes, the situation is more complicated than those questions would suggest. The expansion of Iranian influence - either through proxies or its own commanders and elite fighting forces - into four Arab countries has been opportunistic rather than planned, the result of power vacuums, such as the one created in Iraq after the US invasion in 2003

In Yemen the charge of the Houthis served the interests of several factions both inside the country and beyond. Undoubtedly, the Houthis have been used as cover for the ousted Saleh to reassert his family's authority, principally through his son Ahmed, who is the Yemeni ambassador to the United Arab Emirates and has ambitions to return as Yemen's next president.

As I reported last year both the now ousted Saudi Prince Bandar and the UAE had a hand in opening secret contacts with the Houthis. On one occasion Bandar flew a senior Houthi leader via London for a meeting in Riyadh. Their target was to stop Islah, the Muslim Brotherhood-linked party which was backing Hadi. Such was the concern of this group of Gulf rulers about the staging a counter-revolution to stop the Arab Spring, that they had few qualms about Ahmed meeting the Iranians in Rome to co-ordinate plans to throw the Houthi switch. This meeting was monitored by the US and the information passed onto Hadi.

Since then, the old king has died, and his closest advisers responsible for these disasters dismissed. King Salman has taken charge and is looking with a cold eye on his predecessor's foreign policy failures.

On the eve of the Saudi offensive, Ahmed Abdullah Ali Saleh was warned by King Salman's son not to approach Aden. When Republican Guard units loyal to Ahmed ignored that warning, Riyadh felt a red line had been crossed.

It is now clear that all of these internal Sunni Arab intrigues went wrong. As the Saudi academic Dr Mdawi Al-Rashid has tweeted:

"The Saudi regime is reaping the fruits of the failure of its foreign policy since the beginning of the Arab revolutions which the regime considered a direct threat to the hereditary regime. The Saudi regime stood in the face of the inclination of the masses of all forms especially the Islamic masses, which joined the democratic process and succeeded in the elections. The Saudi regime has reaped the enmity of the most horizontally widespread current in the Arab societies but stood alone and found none but new dictatorships to stand by it."

In Yemen, Islah spoiled the initial plan by refusing to fight the Houthis alone. As a result, the Houthis took more control than was originally intended - not just of the northern provinces but Sanaa itself and then proceeded to mount a full-fledged coup. As it went further south this became increasingly authoritarian and sectarian in character. After three days of demonstrations in the city of Taez, the Houthis opened fire killing eight and wounding 120.

But the fact remains that the chief beneficiary of the disintegrating structure of the Sunni Arab world has been Iran. Its influence as well as field of operations of the Revolutionary Guards has increased. The main question posed by the coalition Saudi has formed - which includes the planes from the UAE - is whether Iran has realised that it has now overreached itself.

This question was put, intriguingly, by another Iranian proxy on whom the Houthis are modelled - Hezbollah. Arabi 21 quotes sources in the "upper elements within the party's leadership" as expressing concern at the repercussions of the Houthi take over in Yemen.

The jubilation of the pro-Shia media at the Houthi advance, the Hezbollah source reported," did not conceal a huge amount of concern" about what is going on there.

"The senior sources within Hizbollah do not conceal their concern that the current Iranian crisis may lead to adopting new and more serious decisions at the level of addressing the raging fires in the region. According to the source who insisted on anonymity, Hizbollah sources say that Tehran believes that Saudi Arabia may not hesitate to extend a helping hand to the Takfiri forces, a phrase used by the Hizbollah leaders, to respond to the take over of Yemen by the Houthis, enabling these forces to launch a series of operations similar to what has been going on Iraq."

This Hezbollah source worried, too, about the reaction Tehran could have to a possible Saudi offensive.

"What the upper circles within Hizbollah fear, according to the source, is that Tehran may decide to open a new front to exhaust the Saudi and Gulf efforts. This may take place in particular within Bahrain and Saudi Arabia by means of mobilising the Shiites in both countries and driving them to take up arms."

Both the Arab coalition led by Saudi Arabia and Iran could now up the ante in each other's territory. If the Iranians have influence over the oppressed Shias in Saudi's eastern province as well as Shia in Bahrain, the same could be said for Arab minorities in Iran. There has been unrest among the Arab Ahwazi minority, who make up the majority in Khuzestan province. The Ahwazi are openly discriminated against in a region rich with oil. They claim they are denied access to fishing and fresh water. On Monday hundreds took part in a funeral procession of a street vendor who immolated himself in protest at the confiscation of his fruit and vegetable stall. On Tuesday a group calling its the military wing of the Ahwaz revolution announced itself in a video on the internet.

Obviously there is not one Iran, but power blocks within it pursuing their own, at times contradictory, agenda. The same Arabi 21 article mentioned criticism within political levels of Hezbollah of the behaviour of Qassim Suleimani, the famed commander of the Iranian Revolutionary Guards, whom they accused of "no longer reading the scene (in Iraq) except through the mindset of a martyrdom seeker."

The recapture of Tikrit from the Islamic State has stalled and the Shia militias have sustained heavy casualties, lacking as they did cover from US aerial fire power. Coffins were arriving for burial in the holy city of Najaf at a rate of 60 a day.

In Syria, the Iranian-backed Assad government is facing losses. Bushra Sham has been captured by Syrian opposition forces and Idlib could fall next.

With Suleimani shuttling between Iraq and Syria, and now a full-scale front opening up in Yemen, wiser and cooler heads in Tehran might conclude that the Guards are overextended. If Iran is indeed on the verge of a historic deal with Washington over Iran's nuclear programme, which would release the country from the economic straitjacket imposed by sanctions, where does its long term interests lie? In re-entering the global economy as an oil exporter or fighting bitter wars in an Arab heartland? Does it really want to pursue an agenda which could only lead to more destructive sectarian strife between Shia and Sunni or should it reconcile itself with its Arab neighbours in a region in which Iran forms a vital part?

- David Hearst is editor-in-chief of Middle East Eye. He was chief foreign leader writer of The Guardian, former Associate Foreign Editor, European Editor, Moscow Bureau Chief, European Correspondent, and Ireland Correspondent. He joined The Guardian from The Scotsman, where he was education correspondent.