Few apart from his small band of fanatical followers will mourn the passing of Aden Hashi Ayro, the leader of Somali’s Islamist insurrection.

As head of al-Shabaab – “the youth” – he is implicated in the murders of 16 foreigners including the BBC journalist Kate Peyton.

But it was during the reign of the Islamic Courts Union that he came to prominence. His few hundred fighters were credited with providing the courts with their military muscle as they took over much of central and southern Somalia the year before last.

Since their defeat in December 2006, at the hands of Ethiopia’s military machine, Ayro has gradually moved away from his former allies in the courts and waged his own Jihadist war against Somalia’s feeble government.

His tactics echoed those pioneered by Iraqi insurgents. His fighters posted videos on the internet warning peacekeepers they would be targeted and claimed responsibility for suicide attacks. Roadside bombs became a daily occurrence in the capital Mogadishu.

Taking out Ayro, who analysts believe trained in Afghanistan with al Qaeda, has been a key objective of US military policy in the Horn.

He was the target of an airstrike last year when US military officials say DNA evidence showed he was wounded. Then, in March, al Shabaab was designated a terrorist organisation by the State Department.

The question now is whether his removal will take the energy out of the Islamists’ Jihad or simply provoke a series of revenge attacks.

The death of such a staunch Islamist could allow the remnants of the courts, based in the Eritrean capital Asmara, to moderate their position and reach an accommodation with the Transitional Federal Government. Or the involvement of US forces in Somalia once again may force them to adopt a more extremist position.

Either way, the short-term effect is likely to be more bloodshed in a country locked in war.

As one analyst told me: “We will see more Ayros certainly and his killing will be interpreted along clan lines, producing more attacks on clans seen as being close to the government, and therefore close to the US.”

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