THE TIP OF A revolutionary iceberg hit Portugal last week--and though Marcello Caetano's dictatorship could still claim control at week's end, it could do so only by ignoring the nine-tenths that remained submerged.

For 13 years, residents of Portugal's three African colonies, Angola, Mozambique, and Guinea-Bissau, have fought a guerrilla war against their Portuguese rulers. An independent Guinea-Bissau won admission to the United Nations last fall, but Portugal continues to control large sections of the other two countries.

In some ways, Portugal's experience in Africa has resembled the U.S.A.'s in Indochina. In both cases, an empire past its peak sought to shore up its imperial defenses, regardless of the cost to the people it was fighting or even to its own people. Portugal, one of the poorest countries in Europe, spends half its budget on its African war, without counting the lives of its young men. There was even a Portuguese My Lai last summer: The Times of London reported in July that Portuguese troops has massacred 400 civilians in a small village in Mozambique. It was the first well-publicized documentation of the indiscriminate killing revolutionaries had long reported and Portugal had tried to cover up.

So it was predictable that, just as the French people turned against their government during the Algerian revolution, just as the American people turned against theirs during the Vietnamese revolution, the Portuguese people would realize that their government's imperialism served the large oil corporations whose African drilling rights it protected, not the ordinary soldiers and working people who did the protecting. And it was predictable that the Portuguese, like their counterparts elsewhere, would bring their war home.

Because the Portuguese government tolerates less dissent than its counterparts elsewhere, it took a much-decorated military hero, General Antonio de Spinola, for four years commander of the colonial troops in Guinea-Bissau, to start the process by writing a book suggesting a Portuguese-African federation. Fearful of even such mild suggestions, Caetano's government cashiered Spinola and suppressed a first wave of sympathetic military revolts. But they were just a first wave. True peace won't come to Portugal till its people stop their government's colonizing in Africa and replace their government with one they control.

TWO YEARS AGO come April, 33 Harvard students occupied Massachusetts Hall to protest Harvard's complicity in Portuguese colonialism. They demanded that Harvard sell its stock in Gulf Oil, whose payments to Portugal for drilling rights in Angola were an important source of income to Portugal. Hundreds of students marched around Mass Hall for a week to make sure there was no police bust like 1969's and to show their solidarity with the students inside.

Harvard still owns its Gulf Oil stock, and Portugal is still in Angola. But last week made it clearer than ever that the occupation of Mass Hall was just a small part of a continuing struggle, a struggle that touches Cambridge and Lisbon as well as Angola, that extends to wherever people fight for control over their own lives and against the vestiges of imperial control. Students here shouldn't forget the Mass Hall occupation, just as they shouldn't forget the battle that went on in Portugal last week and continues in Angola today. Such struggles affect everyone's life, and everyone has a part in them.