Manila — Political parties and movements opposed to the 19-year-old regime of President Ferdinand Marcos face the New Year with an old problem: They are still unable to unite behind one leader.
But now they are trying.
The principal opponents of Marcos have devised a ''fast track'' system for choosing a single opposition candidate. And on Wednesday, 12 of the 14 major opposition leaders signed a controversial ''declaration of unity.''
This document states that if any of them succeeds Marcos, he or she would seek to remove foreign military bases, draft a new constitution, review economic agreements with foreign countries, and legalize the Communist Party. The United States has its two large and strategic military installations in the Philippines: Clark Air Base and Subic Bay naval base.
(According to the Associated Press, State Department spokesman Alan Romberg said the opposition leaders' call for removal of all foreign military bases ''does not specify the timetable for achieving this objective. This is, of course, a compromise statement intended to cover a variety of views and which may be subject to a variety of interpretations.'')
Ideological differences as well as personal ambitions are causing a fissure in the Philippine opposition, making any form of unity forged among the various groups fragile.
The recent absence of Mr. Marcos due to illness sparked efforts to choose a potential common candidate of the opposition for the presidency should emergency elections be held. (Election for president is scheduled for 1987).
But the effort to unify has caused division by leaving out the parliamentary opposition and the nationalist mass movements in the planning stage.
Jaime Ongpin, president of the giant mining firm Benguet Corporation and sympathetic to the opposition, spearheaded the ''fast track'' system. It names possible presidential candidates and proposes a method to choose a standard-bearer without having to undergo the usual political party conventions.
Mr. Ongpin distinguishes this system from other efforts at long-term unity: ''This will apply only if Marcos dies; it is a contingency plan.''
The ''fast track'' system got support from opposition leaders Lorenzo Tanada, Jose Diokno, Aquilino Pimentel, and Corazon Aquino, widow of assassinated opposition leader Benigno Aquino Jr.
But Eva Estrada Kalaw, member of parliament and head of a splinter group of the Liberal Party, rejected the plan, calling it ''undemocratic.'' She said the group has no mandate from the people to set up a succession mechanism.
Salvador Laurel, head of an umbrella group of opposition political parties, the United Nationalist Democratic Organization (Unido), remained tentative and noncommital about it.
Old tensions between those who wanted to boycott last May's parliamentary elections and those who wanted to participate are beginning to surface again. Tanada and Diokno led the move to boycott the polls while Kalaw and Laurel opted to participate.
Not even the looming economic crisis - giving the opposition a chance to map out common strategies and responses - has linked them together.
Yet the opposition leaders know too well that, severely divided, their chances of winning elections against the ruling party machinery are very slim.
Discussions on long-term unification have gone as far as threshing out a concept of a transition government that would rule in the post-Marcos era.
The left-leaning Nationalist Alliance for Peace, Justice, and Freedom has proposed the formation of a ''democratic coalition government'' composed of representatives of political parties and movements opposed to Marcos regime.
What is hard to settle in these talks is the extent of participation of the Communist armed guerrillas in the countryside and the leftist National Democratic Front.
J. Virgilio Bautista, official of the Coalition of Organizations for the Realization of Democracy (CORD), said they cannot ignore the existence of the armed rebels but do not anchor their timetable of protest activities to that of the communists. ''We see areas of complement-ation,'' he said in an interview.
CORD refuses to make elections the centerpiece of the battle against Marcos, but opts for intensified protest in 1985 against the regime, mainly through a general strike that would paralyze strategic industries. The group hopes this strategy would force Marcos to step down.
The opposition will thus pursue its struggle against the Marcos regime on two fronts - inside parliament and outside of it - and in two forms - elections and mass actions. When these forms of protest cross paths, the question of unifying them will have to be addressed once more.