United Nations, N.Y. — The Palestine Liberation Organization (PLO) appears to have made an important policy shift. According to a well-placed Western diplomat, the organization headed by Yasser Arafat apparently has abandoned its recent moderate approach toward the United States and the Western powers -- and, indeed, has lost patience with them altogether.
The apparent PLO decision to take a road that will lead it into confrontation with the United States took diplomats at the United Nations by surprise. For the past year, the Palestinians had followed a cautious diplomatic strategy, closely coordinated with European Community countries.
Its objective was to project a respectable image and gradually to gain the support and recognition, first of Western Europe, later of the US.
But the recent US vote on Israeli settlements in the occupied West Bank -- the one that later was termed a "mistake" by President Carter -- apparently convinced the PLO leadership that it could not expect the US ever to move away from the Israeli positions.
Until very recently, the PLO had agreed to be patient, in exchange for West European support. The members of the European Community had led the PLO to believe that if the Israeli-Egyptian autonomy talks did not produce results by the May 26 target date, they would make their own move at the Security Council toward mid-July.
But as a result of the Iran crisis, the Europeans have not been able to give the PLO all the assurances expected. America's allies are reluctant to forsake it during the US election campaign and when the hostage crisis could set the Middle East aflame.
With West Europeans unable to pledge future support, the PLO moderates at a recent meeting in Beirut, Lebanon, could not justify a further delay in pressing for action, which radical elements demanded.
It is against this background that the United States found itself on April 30 in the position of vetoing a Security Council resolution strongly favored by the PLO. The resolution aimed at establishing a Palestinian nation and called for Israeli withdrawal from all Arab territories, including Jerusalem.
The PLO's UN observer, Zehdi Terzi, disappointed with the US veto, said afterward that a special session of the UN General Assembly would be called to deal with the Palestinian situation.
The convening of such a session, expected in June or July, would have a number of objectives, some of them unfavorable to the US. According to analysts here, it could:
* Isolate the US as Israel's major friend, and perhaps drive a wedge between the US and some of its own friends, such as Saudi Arabia and Morocco.
* Give the Soviet Union an opportunity to get back at the US for the special UN session on Afghanistan last January, which strongly condemned the Soviet action.