Movements in the last two days by the Israeli forces advancing across Lebanon, coupled with oblique hints by senior Israeli officials, suggest that a much more far-reaching strategic objective has been mapped out by the Israeli government thus far.

With its armored columns poised to cut across the vital Beirut-Damascus highway, and the open option to link up with Christian Maronite forces north of it, Israel's publicly stated goal of establishing a 25-mile Palestinian-free buffer zone across the Lebanese border now appears merely a fallback position in case its armored columns are stalled by Syrian intervention or if international pressure forces a political solution.

Israel's undeclared, and much more ambitious objective in Lebanon now appears to be the redrawing of the political landscape of the war-shattered country. What will emerge, it hopes, will be a friendly neighbor free of Palestinian or Syrian dominance.

Amid a virtual news blackout on details of the invading force's tactical movements in Lebanon, senior Israeli officials today hardly were prepared to acknowledge that this is their long-range strategic objective.

The official line in the government of Prime Minister Menachem Begin is that Israeli forces are interested for the moment only in pushing the Palestine Liberation Organization's guerrilla forces beyond artillery striking range of civilian settlements in Israel's northern Galilee region and ending the threat of cross-border terrorism.

Aides to the prime minister have said that current Israeli Army operations far north of the 25-mile zone are complementary to securing the southern region and aimed at ensuring that Palestinian guerrillas do not return to the border region after a cease-fire is arranged.

Depending upon the outcome of a negotiated cease-fire, Israeli officials say, the new artillery-free zone could be policed either by an enlarged U.N. peace-keeping force, or a new multinational peace-keeping force shaped along the lines of that now in the Sinai Peninsula, or a combination of the two, possibly with regular Lebanese Army troops and Israeli-supported Christian militias in southern Lebanon led by renegade Maj. Saad Haddad.

Diplomatic sources and Israeli military analysts note that while the Beirut-Damascus road has enormous tactical potential for the rapidly advancing Israeli forces, retaining control of it poses something of a dilemma for Israeli military planners.

A move west by the invading force could divert Syrian forces south of Beirut away from Israeli columns moving northward toward the capital, but it also could alarm Syrian President Hafez Assad so much that he might decide on an even wider ground conflict with Israel. Similarly, a move eastward toward Damascus might divert Syrian forces south of the highway away from Israeli forces moving in the central sector, but it also could push Assad over the brink and lead to a general Middle East war.

If, on the other hand, the Israeli armored columns cut across the highway and link up with the Phalange forces of Bashir Gemayel in the mountains north of the highway, the Israeli Army would be in a position to control the central Chouf range that runs the length of Lebanon southward nearly to the Israeli border. Lebanon, in effect, would be cut in half by the invading forces, with Israeli columns in control of both the Mediterranean coastal region and the sector just east of the Chouf. If Syria decided not to press a full-scale confrontation with Israel, its Army could redeploy eastward across the Bekaa Valley and await a political settlement.

To Israel's advantage, the Chouf range south of the Christian-controlled area above the Beirut-Damascus road has a large population of Lebanese Druzes and Shiite Moslems, many of whom would welcome an end to PLO dominance of their region, according to the view of some military analysts.

One of them, Chaim Herzog, former chief of military intelligence and a former Israeli ambassador to the United Nations, observed in a Voice of Israel radio interview today, "If the idea is to link up with the Christians and the Beirut-Damascus road remains open, it may just be an indication of an attempt to create a new political situation and . . . indicate there is a possibility to emerge from the impasse that was created by the PLO stranglehold on a good part of Lebanon and to bring back Lebanese sovereignty."

Herzog added, "For the first time, the Lebanese themselves are beginning to see prospects of Lebanon becoming a country again and achieving its independence."

Indications that Israel intends to significantly alter the political face of Lebanon seemed borne out by an Army command announcement tonight after it said Army units captured the coastal town of Damour, south of Beirut.

Damour, the Army command said, is a "previously prosperous Christian town but in recent years the Palestinian terrorists drove out the Christian inhabitants. It is our intention to restore the previous Christian glory and to prevent a return of the terrorists."

The announcement added, "The IDF Israeli Defense Force invites the Christian inhabitants to return to their homes when the battle subsides and after the appropriate indication to do so is given." It said the Israeli government will help the Christians rebuild homes that were destroyed by the PLO guerrillas as they retreated.

When asked today how Israel intended to bring about an independent Lebanon as a result of the invasion, a senior Israeli government source replied, "If you eliminate the presence of the PLO in Lebanon, you certainly increase the chances for Lebanon's independence, don't you? The PLO is a foreign organization in Lebanon. It is the cause of all the ills of Lebanon."