Shortly after dark on September 16, 1982, small units of Christian militiamen, about 150 men each, began entering the narrow alleyways of the Sabra and Shatila Palestinian refugee camps from their staging ground at Beirut's international airport.
From that Thursday evening until the following Saturday morning, about 2,000 of the militiamen, known as Phalangists, liquidated all traces of humanity in the camps.
According to Red Cross estimates, up to 1,000 unarmed men, women and children were shot, hacked and trampled to death.
The immediate cause of the massacre was the assassination two days earlier of the Lebanese president Bashir Gemayel, a Maronite Christian and a patron of the Phalangists, by a member of a pro-Damascus political party.
The proximate cause, however, was Israel's oft-repeated demand to their Christian militia allies in Lebanon that they "clean out" West Beirut of Palestinians, as Israel's then-defence minister, Ariel Sharon, put it. Although it has never been established conclusively that Israeli officers ordered the militias into Sabra and Shatila, the killers entered the camps with Israel's knowledge and approval.
Israeli forces also put up a cordon around Sabra and Shatila as the killing took place and lit up the night-time sky above the camps with flares to facilitate the "clean-up".
More critically still, as later official Israeli investigation showed, Israeli military officers were fully aware of the thirst for revenge that fuelled the militiamen following Gemayel's death. Despite their involvement in the bloodletting in Sabra and Shatila, no Lebanese or Israeli has ever been prosecuted for the killings there.
Although the slaughter was small by the standards of the other especially heinous massacres in recent Middle East history - in Syria's Hama in 1982 and Iraq's Halabja in 1988 - it is a milestone worth noting 30 years later for two particular reasons. The equation of "Muslim" with "terrorist" predates the aftermath of September 11, 2001. It was fully part of the lexicon of Israel and its Lebanese allies in 1982, fuelling the atmosphere that made Sabra and Shatila possible.
"Women give birth to children, and children grow up as terrorists," replied one Christian militiaman outside the camps after he was asked by Israeli soldiers why he and his people were killing women and children. The massacre also wrecked Israel's geopolitical dreams. Israeli armed units marched all the way into Beirut prompted not only by the desire to rid the city of the Palestine Liberation Organisation, but by the geopolitical fantasy that it could remake Lebanon and engineer a regime to its liking. Sabra and Shatila proved it horribly and tragically wrong.
* The National