Historians date the battle of Zahleh from this day, when Lebanese Forces fighters beat off a Syrian attack on the town and a siege of some 90 days began. Ménargues says Syrian heavy guns killed 50 and wounded over 200 that day in Zahleh and the Christian zone north of Beirut.

Ménargues dates a day of intensive shelling of Zahleh, with about twenty dead, to 6 April.

Ménargues writes that Syrian special forces, landed by helicopter at dawn on 10 April, soon took the heights of Qalaat Aramta and Deir Charfé around Zahleh, leaving its defenders almost encircled.

According to Ménargues, Bashir Gemayel answered the collapse of a cease-fire on 22 April, which left 140 dead or wounded in Beirut within hours, by having the international airport shelled. On 11 May US ambassador John Gunther Dean urged the Lebanese Forces, via Alfred Madi, to let it reopen; that evening they dropped their objection.

Ménargues has two Syrian helicopters downed: a Mi-8 supply craft, hit by F-15s around noon just after leaving Rayak, and a French-built Alouette late in the day; in between, jets struck ADF positions around Sannine. Israel acted at Christian leaders' request once Syria held Sannine's summit; next day Syria answered with surface-to-air missiles in the Bekaa.

According to Ménargues, Syria's foreign minister Abdel Halim Khaddam brought a five-page paper to Baabda on 5 May. In effect a Lebanese–Syrian accord on institutions, politics, the economy and culture, down to school curricula, it was rejected by the Kataeb leader Pierre Gemayel.

In Ménargues, the 'red line' between Sohmor and Yohmor in the southern Bekaa was occupied on 7 May by 7,000 Syrian troops: two brigades backed by tanks and heavy guns.

Ménargues writes that Habib came from Damascus by road on the evening of 7 May, Beirut airport being closed. De Clerck and Malsagne date Reagan's dispatch of Habib to 4 May.

For 8 May, a day of shelling throughout Habib's meetings, Ménargues gives the US embassy toll: 21 dead and 98 wounded.

Ménargues's run of drone losses begins on 14 May, when a Syrian SAM-6 downed an Israeli reconnaissance drone over the Bekaa; more were lost on 19, 22 (two) and 25 May.

The meeting was called after Begin told the Knesset on 4 June of his promises to Lebanon's Christians. The Arab envoys asked Bashir Gemayel to break with Israel; he demanded guarantees in return (Hanf, Ménargues).

Ménargues has some 600 Internal Security Forces gendarmes entering Zahleh on 30 June, ending the siege, and the 95 fighters from outside the town leaving by bus over a mountain road behind a Syrian colonel's car, past Syrian troops posted along it; Hanf says they left under Saudi escort. Siege toll: 200 dead and over 2,000 wounded (Ménargues), over 200 and 2,000 (de Clerck and Malsagne), 300 and 3,000 by the Phalange's count (Fisk).

Ménargues lists the participants as Syrian foreign minister Abdel Halim Khaddam, the Arab League's representative and the Saudi and Kuwaiti ambassadors, Ali Chaër and Abdel Hamid Bouayajane. That day a general strike against the Syrian presence shut down the Christian regions.

Bashir Gemayel's pledge took the form of a letter to President Sarkis dated 6 July, which Sarkis never published (Ménargues).

Ménargues counts 6 dead and 20 wounded in the two raids, on Democratic Front sites at Habbouch (near Nabatiyeh) and Ghaziyeh (near Sidon). Hanf dates the Israel–PLO 'Fourteen Day War' from them.

Ménargues counts six bridges over the Awali and Litani destroyed in the raids. The Palestinians replied the same day with some 2,000 shells and rockets on Nahariya and Kiryat Shmona.