Saudi Arabia’s escalating intervention in Yemen is a high-stakes gamble that risks back-firing in a series of complex ways, ultimately endangering Saudi oil infrastructure and the security of global energy supply.

Military analysts say there is little chance that air strikes by a Saudi-led coalition of Sunni countries will subjugate the Iranian-backed Houthi forces in Yemen. It may require a full-blown invasion by land forces to secure control. Large concentrations of Saudi armour and artillery are already massing near the border, though this may simply be a negotiating ploy.

The longer the conflict goes on, the greater the risks that it will stir up internal hatred in a country that has traditionally been relatively free of sectarian violence. Adam Baron, from the European Council on Foreign Relations, said the inflammatory comments about the Sunni-Shia struggle by politicians across the region are becoming “self-fulfilling prophecies”.

Al-Qaeda in the Arabian Peninsular (AQAP) – thought to be the most lethal of the jihadi franchises, and a redoubt for Saudi jihadis – already controls a swathe of central Yemen and is the chief beneficiary of the power vacuum.

AQAP can plan terrorist strikes against Saudi targets from a deepening strategic hinterland with increasing impunity. All US military advisers have been withdrawn from Yemen, and much of the country’s counter-terror apparatus is disintegrating. It is becoming harder to harry al-Qaeda cells or carry out drone strikes with precision.

The great unknown is whether a protracted Saudi war against Shia forces in Yemen – and possibly a “Vietnam-style” quagmire – might tug at the delicate political fabric within Saudi Arabia itself. The kingdom’s giant Ghawar oil field lies in the Eastern Province, home to an aggrieved Shia minority.

“If the Saudis continue this war – and if they keep killing civilians – this is going to create internal instability in Saudi Arabia itself,” said Ali al-Ahmed, from the Institute for Gulf Affairs in Washington.

Large numbers of Saudi youth are disaffected. An estimated 6,000 have been recruited by al-Qaeda and a further 3,000 have fought for ISIS in Syria and Iraq. While the Saudis have a formidable security apparatus, with a 30,000-strong force guarding the oil infrastructure, the risk of infiltration is high even among clans linked to the royal family.

Two al-Qaeda suicide bombers in a pipeline attack in 2006 were scions of the ruling elite, one a close relation of a leading Wahhabi cleric and the chief of the religious police.

David Fuller's view

The perpetually troubled Middle East is rapidly sliding into the world’s most dangerous power struggle, with potentially international implications.  For once the epicentre of tensions in the region is not Israel’s perennial struggle with the Palestinians.  Moreover, this crisis cannot logically be blamed on American intervention in the region, although a few commentators will inevitably persist with this theme for political reasons.

Instead, the problem is a long festering religious virus which predates US interests in the Middle East by many decades.  It is the Sunni-Shia hatred, barely contained by vast oil wealth, which has now metastasized across the region following the collapse in oil prices.  The opposing factions are led by Saudi Arabia and Iran.  Needless to say, the implications would be much more dangerous for the Middle East and also the world if nuclear weapons are developed in Iran.  That would cause Saudi Arabia to respond by purchasing nuclear weapons, possibly from Pakistan. 

Fortunately, this is not an immediate threat although the Sunni-Shia war is likely to fester.  However, a few years from now the risks could be much greater.  We would not be able to rely on a US-Soviet standoff due to mutually assured destruction, because several countries in the Middle East are capable of developing or more likely acquiring nuclear weapons.  That would obviously increase the risk of them being used. Meanwhile the Sunni-Shia conflict is escalating.  This has the capacity to firm oil prices which could otherwise be somewhat lower due to current surplus capacity.