THE news is welcome indeed that the US Marines are within a week or so of completing the pullout from their land base in Lebanon. This marks a welcome acceleration in the timetable. In the days immediately after President Reagan's transfer order, some administration officials had held that three or four months might be required.
But the situation in Lebanon has been so unstable that faster redeployment to ships offshore was wise, and is now being accomplished. It has been clear for some days that the United States no longer has a significant role to play in the Lebanese conflict.
Even as the US withdraws, Israel is again making its presence felt, implicitly warning Syria and all Lebanese factions not to permit the Palestine Liberation Organization to reestablish military bases in Lebanon. Israel has conducted bombing raids on what it said were Palestinian guerrilla bases in three Lebanese villages. Also, it was widely reported over the weekend that at least one Israeli armored column penetrated north to within some 15 miles of Beirut, from the southern Lebanon area held by Israel.
Israel's concern about the security of its northern frontier is wholly understandable, inasmuch as there is no effective government now in Lebanon. Israel does not want a repetition of recent history in the terrorist attacks that were mounted against it from southern Lebanon.
Yet Israel needs to exhibit caution, particularly in its ground penetration of Lebanon. It would not he helpful to Lebanon, nor to Israel itself, for Israeli military forces to become involved once again in ongoing warfare in Lebanon.
Meanwhile the major active outside diplomatic player at this time, Saudi Arabia, is continuing its effort to bring peace to Lebanon. Saudi emissaries have been shuttling from Damascus, Syria, to Lebanon, trying to get Syria's President Assad and all Lebanese factions to agree on a peace plan. The effort remains under way at this writing, notwithstanding the fact that Mr. Assad and several Lebanese Muslim factions rejected the original Saudi plan until - or unless - President Gemayel abrogates the May 17th treaty with Israel and agrees to consider the withdrawal of Israeli and Syrian forces as two separate issues.
The backdrop to the diplomatic activity is the implicit threat of major military attack by Muslim forces against the remnants of the Lebanese Army.
Yet at this writing the military situation in Lebanon is in something of a hiatus, despite shelling of Souk al Gharb by Druze gunners. This hilltop town, still held by the Lebanese Army, is a gateway to the Presidential Palace and Beirut itself.
Lebanon has seen too much fighting and destruction. The current diplomatic effort, however challenging the tasks it faces, is far preferable to renewed all-out warfare. The diplomatic efforts deserve encouragement.
And as they are going forward, it is proper for the US Marines to continue their prompt shift from the airport base to stations on American ships offshore. It now is for other nations to play the major roles in Lebanon, including the role of peacemaker.