The war in Lebanon has taken an unacceptable turn with Israel's killing of four UN peacekeepers. Enough is enough - Israel and Hezbollah guerillas must lay down their weapons and allow the deployment of peace monitors to keep them apart so that a stable atmosphere for negotiations can settle.
No human life is worth more than another. Nonetheless, the killing by Israeli forces of the United Nations military monitors is an outrage. A line has been crossed. Hopefully, this appalling act will shock the world into taking urgent action to bring hostilities to an end.
There has, justifiably, been concern since the start of the conflict 15 days ago that Israel's response to rocket attacks and the kidnapping of two soldiers by Hezbollah was disproportionate. Israel's bombing raids have since killed more than 400 civilians, destroyed billions of dollars of infrastructure and caused a humanitarian crisis with half a million people homeless and lacking security, food and medicine.
About 20 Israeli civilians have been killed by rockets and the militia has warned it can widen the area of the Jewish state under threat by using longer-range missiles, putting hundreds of thousands of Israelis at risk.
Breaches of the rules of war are being committed on both sides. The first Geneva Convention was drawn up almost 150 years ago, and others have followed since, notably after the carnage of the second world war. They seek to limit the suffering of those affected by conflicts.
Policing the conventions is no simple matter. There is no such occurrence as a 'perfect war', after all; war breaks out because sides cannot amicably resolve differences and in the heat of battle, minds can turn to finding the best path to victory rather than keeping to the rules.
This is especially true in the post-September 11 environment of terrorism. Israel and its top ally, the US, have labelled Hezbollah a terrorist organisation and since the opening shots of the so-called 'war on terrorism' in Afghanistan in 2001, elimination of the threat has been the foremost objective.
Israel's insistent approach, coupled with Hezbollah's strategy of operating among civilian supporters, has had devastating consequences for the Lebanese. But whether the Israeli military's deliberate targeting of buildings where it believes Hezbollah has rocket batteries, knowing that civilians are also living there, is a war crime is a matter of interpretation. At the least, it is a breach of the conventions.
Hezbollah is certainly committing war crimes, though - the group is blatantly firing rockets into Israeli towns and cities, the eventual target unknown and unseen. In Israel's case, its military is knowingly causing civilian hardship on a scale that far exceeds its objectives. Whatever the legal technicalities, the indiscriminate killing of so many civilians is morally indefensible.
The deaths of the military monitors raise uncomfortable questions. Why Israel, operating in a part of south Lebanon it has previously occupied and whose geography it knows intimately, attacked a bunker where blue-helmeted monitors from Austria, Canada, China and Finland were sheltering is unclear. No warning was given to the military monitors to allow them time to escape and appeals from them for the attack to cease were apparently ignored. Israel must explain how this came about.
If the Israeli intention was to draw international attention to a conflict that too many nations have chosen to turn a blind eye to, it has dramatically succeeded. The US, Britain and others with a critical role to play in negotiating a solution have no choice now but to intervene.
A ceasefire must be initiated immediately and foreign peacekeepers with powers to disarm sent in to ensure it holds. Negotiations should swiftly follow.
Ending 2,000 years of religious differences will not happen soon. But the utmost effort must be taken by all involved to find a lasting peace.