Hamas leadership and the international media, understandably, immediately accused Israel’s Mossad of being behind the killing of Mahmoud al-Mabhouh in a Dubai hotel room two weeks ago.

There is no shortage of reasons for this. Mabhouh, for the last six years, was the main Hamas operative in the complex arm-smuggling organisation linking the Gaza Strip and Iran. Israel’s intelligence services have been fighting a major campaign against this pipeline, largely in secret.

A long string of Hamas and Hizbollah members involved in the shipments have died in mysterious circumstances; ships have disappeared from the high seas; a convoy was attacked from the air last year in Sudan.

The periodical air-strikes against the Rafah smuggling tunnels under the Gaza-Egypt border are, as Israel Air Force Chief, Major General Ido Nehushtan, says “only the end of the nozzle of the toothpaste tube”.

Mabhouh would have been a target also for historical reasons. This founding member of Hamas was behind the kidnap and killing of two Israeli soldiers in 1989 and Israel has a long memory when this kind of thing is concerned. The timing of the assassination, when the talks over a prisoner swap for captured IDF soldier Gilad Shalit have once again frozen up, is significant.

But there is also least one major reason to consider other assassins. Most of the alleged targets of the Mossad in recent years were in Lebanon, Syria and Iran. Dubai is a country which Israel is hoping to keep away from the radical axis. It even hosted an Israeli minister for an international conference two weeks ago.

If carried out by Israel, the killing would have needed prime ministerial sanction and Binyamin Netanyahu has bitter memories of an assassination attempt in a “friendly” Arab country, Jordan, that went wrong in 1997.

There are three other plausible alternatives. Mahbouh spent a year in an Egyptian prison and he was also wanted in Jordan.

Israel is not the only Mideast player worried about the burgeoning Iran-Hamas-Hizbollah axis, which has already been used to smuggle arms to terror organisations operating in several Arab countries. All of them could have had a motive to get rid of Mahbouh.

The killers might not even have been sent by a government. Mahbouh was in a high-risk career, international gunrunning.

His death could have been payback for a deal gone wrong. Which leads to another possible suspect – the supplier. Mahbouh may have been taken out by his notoriously paranoid Iranian patrons, who could have turned against him for any number of suspicions.

None of these three latter options, of course, rule out Israeli involvement. For the purpose of a hit in Dubai, the Mossad could certainly have preferred to use subcontractors, either knowingly, or by planting disinformation, suspicion and discord in the right places.

Whatever the truth, the killing will be ascribed to the Mossad anyway, further bolstering the image of the organisation and its chief for the last eight years, Meir Dagan, as being capable of any act of daring skullduggery in Arab capitals.

It also highlights the dilemma of Hamas whether or not to carry out attacks on Israeli targets abroad; its lack of an international operations infrastructure; and more than anything else, the continuing failure of Hizbollah to avenge the death two years ago of its military chief, Imad Mughniye, in a mysterious car bomb in Damascus.