Enough of this Keith
These are the facts as I know them – I've become tired of your unqualified claims; if you have any evidence that they aren't correct, produce it
The Israelis suspected that Sabra/Shatila was full of weapons and fighters "The Israelis maintained that 2,000 to 3,000 "terrorists" remained in the camps, following Israeli guidance on how to enter it. The forces were mostly Phalangist, though there were some men from Saad Haddad's "Free Lebanon forces""- Wiki

Despite Israeli claims, neither weapons nor fighters were found, in fact the killers met with no armed resistance whatever from the refugees.
Knowing the bad blood between the Christian militia, 1,500 militiamen assembled at Beirut International Airport, then occupied by Israel. Under the command of Elie Hobeika, they began moving towards the area in IDF-supplied jeeps, some bearing weapons provided by Israel, (above link).
The Israelis drove the militiamen to the camp, opened the gates for them, and set up a base within range– they had previously fired shells into the camps.
"During that period, Israeli units were sporadically firing artillery rounds into the Sabra and Shatila camps, although no fire was being returned because the last PLO defenders had been evacuated two weeks earlier, and any arms larger than handguns had been collected at that time.
At noon Thursday, Sept. 16, a delegation of five old men bearing white flags tried to negotiate an end to the shelling of the two camps by the Israeli forces, which had now surrounded the camps and sealed the exits. Four of the Palestinian negotiators were killed. At 5 p.m. the first 150 Phalangist militiamen entered the camps and at 5:30 Israeli forces began firing flares over them to illuminate the narrow, twisting alleys, where massacres had already begun in one area only 100 yards from the nearest Israeli observation post. At this point mobs of Palestinian women began rushing to nearby camp exits, seeking to escape. Israeli tanks, stationed at 100- or 200-yard intervals and blocking all exits, turned back everyone. Israeli officers have testified that it was about this time that they first heard the order to kill the women and children, as well as the men, relayed over a walkie-talkie by militia commander Elie Hobeika, from the command post he shared with the Israelis. Israeli units continued firing illumination flares over the camps, a pattern they maintained throughout Thursday and Friday nights.
Starting Thursday evening, horribly wounded victims began pouring into two hospitals in the camps, and the airwaves were full of commands revealing what was going on inside, and queries from Israeli officers and enlisted men, who could not believe that their commanders realized that whole families were being slaughtered in front of their eyes. When two Israeli officers stationed in adjacent tanks began discussing with each other the executions of children they were watching, the voice of General Amos Yaron, commander of Israeli forces in Beirut, came on the air to warn them against such talk on the military radio."
WASHINGTON REPORT

The Phalangists slaughtered up to 3,500 of the occupants, raping the women then cutting their throats – corpses of pregnant women who had been disembowelled and their dead children ripped out were found throughout the area.
The Israelis provided illumination so the slaughter could be carried out throughout the night.
At the end of three days, the Israelis ordered the Falagists to stop and began to hide the evidence of the massacre with bulldozers.

"By Friday morning Israeli army bulldozers had arrived. While the Phalangist militiamen rested, corpses were bulldozed into a mass grave and Israeli soldiers sent food and water across the barricades to the militiamen. Word of what was going on spread rapidly throughout Beirut. Ze'ev Schiff, military correspondent of the Israeli daily Ha'aretz, began telephoning Israeli officials, including Minister of Communications Mordechai Zippori. Zippori telephoned then Foreign Minister Yitzhak Shamir."
(Report from Washington link)

The Falangists were driven away – none were ever arrested or charged.
Jewish American nurse, Ellen Seigal, was present throughout the three days, treating the wounded, she was a loyal support of The State of Israel and gave evidence to the Kahan Enquiry.
Since the massacre she has dedicated her life to telling the world what happened over those three day.
HEROES OF SABRA SHATILA

Israel facilitated the massacre, they helped arm the killers, they illuminated the slaugher, they prevented the victims from escaping and survivors claim Israeli soldiers were seen in the camp while the killing was taking place:
"The Israel Defense Forces surrounded the Palestinian refugee camps, controlled access to them, and facilitated the massacre by firing illuminating flares over the camps.[5][6] In 1982, an independent commission chaired by Sean MacBride concluded that the Israeli authorities or forces were, directly or indirectly, responsible.[7] The Israeli government established the Kahan Commission to investigate, and in early 1983 it found that Israeli military personnel were aware that a massacre was in progress without taking serious steps to stop it. Therefore it regarded Israel as having indirect responsibility. The commission held Ariel Sharon personally responsible for having disregarded the prospect of acts of bloodshed by the Phalangists against the population of the refugee camps and not preventing their entry.[8] METAPEDIA

That is how I understand the events – if you have any evidence that this did not happen, produce it Keith – your one man campaign to rewrite history is sickening
Jim Carroll
By the way, the article and others from The Washington Report (published by the American Educational Trust) is well worth reading in full