Though a vague diplomatic way out of the desperate Israeli-Palestinian conflict in Lebanon seemed to be taking shape July 6, Israeli and Phalangist hawkishness appeared to foreshadow a grim battle for Beirut in the days ahead.
The plight of the 500,000 citizens of west Beirut was worsening. And Israeli officers were hinting that if diplomacy did not gel by the end of the week, the military would be sent into Palestinian strongholds.
The diplomatic approach of US envoy Philip C. Habib apparently centered around four points: (1) the departure of Palestine Liberation Organization leaders and the 5,000 to 6,000 guerrilla fighters from Lebanon to various Arab countries, (2) return of Palestinian refugees in Lebanon to their camps, (3) perhaps a token PLO political presence in Beirut, and (4) deployment of the Lebanese Army or a multinational force to police western Beirut.
This is a basic rehash of a diplomatic plan that has been advocated by Lebanese and American officials for three weeks, and there are few public statements by Israeli and PLO leaders that indicate new support for this plan.
The newest twist July 6 was a Reagan administration proposal that United States Marines would supervise a sealift of Palestinians from Lebanon. Analysts here felt it was unlikely the PLO leaders would agree to leave the country under the supervision of the US, the nation they most closely identify with Israel.
''What we seem to have now are a handful of straws that every diplomat is clutching at,'' a Western diplomat told the Monitor July 6.
''While it is conceivable that the PLO leaders would rely on the United States to evacuate them, it seems far from probable. You've still got to ask where they are going to go, how many are going to go, what happens to those who stay.''
This diplomat reported that Israeli officials had been informing Western countries that July 9 is the deadline for a diplomatic settlement and that after that the military option looms largest.
The biggest obstacle to political agreement on evacuation of the PLO, he said , was division within the PLO central committee and the inability of guerrilla leaders to guarantee their followers' acceptance of any agreement to leave.
''There are still too very many places where agreement is breaking down,'' the diplomat said. ''I think that Palestinian leaders simultaneously are engaging in massive wishful thinking, hoping that some miracle changes their situation.''
Israel's chief Lebanese ally, the right-wing Phalange, appeared to be hardening its position toward the PLO. The Phalange called up for military service some 2,500 to 3,000 1982 high school graduates, bringing troop strength up to 10,000 regulars. Though a Phalange official said the move was planned for many months, the call-up makes the Phalange far and away the strongest factional group in Lebanon.
A Phalange official told the Monitor his party would not tolerate even a ''face-saving'' presence in Lebanon and believed that Israel would soon embark on a ''delayed military solution'' to the west Beirut problem: ''Israel can't stop where it is now.''
He said Arab leaders had tried last week to convince Phalange chief Bashir Gemayel to let a token PLO presence remain in Lebanon and that Mr. Gemayel had flatly refused - based on the principle that ''any symbolic presence will develop into an effective military presence that will bring us back to where we were before June 6,'' the day of the Israeli invasion.
Thus, it seemed that even if the PLO could agree to the vague diplomatic plan that is being talked about, the Phalange, by objecting, could derail that plan. The hawkishness of the Phalange and the ever-closer Israeli-Phalangist cooperation (soldiers of both armies are on joint patrols throughout the Beirut area these days) were factors that could influence Israel to be even less conciliatory toward the PLO than it has been until now.
Less than 24 hours after the latest cease-fire, the guns of war began sounding loudly again between east and west Beirut. Israeli officers at their headquarters in the Beirut suburb of Baabda appeared to be preparing public opinion for the next step - whether it is PLO evacuation or annihiliation.
Col. Paul Kader suggested that ''once the PLO problem is removed'' peace in the Middle East could be advanced. He spoke also of the ''eradication of restraints'' that the PLO had imposed on Arab countries regarding relations with Israel.
Colonel Kader also said that while there was ''no published deadline'' for diplomatic efforts, ''we seem close to the end of the negotiating process.''