The three incidents on Monday and Tuesday, in Tbilisi, New Delhi and Bangkok are somewhat baffling to Israeli security experts.

On the one hand, the nearly simultaneous operations in different parts of the globe point to a highly organised network with major resources at its disposal.

On the other, the attacks appeared bungled and the targets were all "low-grade".

The wife of an obscure Israeli representative was wounded; an easily detected device was planted under the car of a Georgian employee of the Israeli embassy in Tbilisi; and one would-be assailant managed to blow his own legs off.

All this makes it hard to believe that they were carried out by Hizbollah or the Iranian Republican Guards Al-Quds Force, both top teams in the Premier League of international terror.

This apparent contradiction has led to two theories. One is that the attacks were carried out by a less sophisticated outfit, perhaps in the hope of receiving Iranian funding. The second is that these attacks were actually carefully calibrated by the planners so as not to make the Israeli government so angry that it would feel justified in wreaking havoc on Hizbollah's military apparatus in Lebanon.

There is also a third explanation which does not necessarily rule out the previous theories:

"There is nothing new or surprising in what happened this week," said a veteran Israeli defence official. The other side has been trying very hard, again and again, to hit targets around the world, especially since the assassination of Hizbollah operations chief Imad Mughniyeh, for which they blame us.

"They choose these targets so as not to provoke us too much and so it seems as if there are so many of them that at least somewhere we will let down our guard."

One senior government analyst warned: "One of the worrying signs is that Iran seems to be more desperate than usual to carry out an attack and may be willing to take bigger risks than usual. We saw that with the plot to assassinate the Saudi ambassador in the US."

Anyone who has ever visited an Israeli embassy, anywhere in the world, is aware of the multi-layered security protecting the building and the diplomats. Israel's representatives abroad have been considered prime targets long before the foundation of Hizbollah, back in pre-Islamic revolution days when the Israeli flag flew over the embassy in Tehran. These remain facts of life for Israeli diplomats and their families abroad.

Their safety will continue to rest on Israeli security and co-operation with local intelligence services.