PORTUGAL, a poor European country, for the past decade has been bombing and shooting liberation forces in three of its African colonies. The Portuguese soldiers who care carrying out the ruthless colonial policy of their fascist government are mostly poor peasants from Portugal's interior who are drafted into service. Some of the colonial troops, as is true in any colonial war, even are natives of the three colonies. They are all prisoners of circumstance, ignorant of the great social forces that toss them around like so much dust. In an immediate sense, they are blameless for the atrocities they commit every day. And yet, innocents that they are, liberation force bullets can make no distinction between them and those who send them into battle.

Such is the awesome tragedy of revolution, a tragedy just re-enacted in Chile, a tragedy that has always posed a wretched dilemma for the Left. Socialists, believing that men and women are products of their social circumstance, can hardly pin any ultimate blame on those who stand athwart the path of revolution. And yet the imperatives of a situation quite often seem to dictate that those people who impede progress be removed, at times forceably and violently removed.

The final crescendo of middle-class rebellion that toppled the socialist government of Salvador Allende was led by Chilean truck owners, whose month-long strike against Popular Unity caused the shortages which helped cripple the government. Most of the truck-owners were not giant monopolists, but small businessmen, owners of one or a few trucks who were honestly fearful that Popular Unity planned to expropriate their property. They acted from fear, a fear that their world was about to be shattered. They could have acted no other way. And yet they helped overthrow a government dedicated to greater freedom and justice for all Chileans. They killed a good and decent man. They are blameless, but they are responsible.

The Left dilemma was posed anew by the military takeover in Chile. As the dictatorship fastens its hold on the country, as the generals with the sunglasses issue orders for more executions, the debate that has divided the Chilean Left in recent years will flare up once again on a world scale, just as it has so many times before in this century.

On the one hand are the Activists, who argue that peaceable revolution is impossible. Capitalist society, they say, is ridden with internal contradictions, which only become more intensive as the pace of revolutionary change increases. The old ruling class will never surrender its dominance without a struggle; to think otherwise is wishful dreaming. Best to seize control of the state or another instrument of violence and repress the right before it has a chance to move against socialism.

Arrayed within the Left against the Activists are the Legalists, who are strong in nations that have achieved political democracy. Revolution, they argue, will certainly be a chaotic upheaval, but it need not include a campaign of violence orchestrated by socialists. Political democracy can be the tool to expand economic and social democracy peacefully, attracting growing support from the middle classes and isolating the old rulers so that violent resistance is obviously futile.

The Legalists, who are certainly as dedicated as their Activist opposition, argue quite sensibly that socialism means--for both groups--the widest possible extension of democracy into the social and economic sphere. Why, then, take a chance on sacrificing political democracy for extra-legal tactics that have no built-in certainty of success?

Moreover, once abandoned, any democracy at all may be hard to recover after the swirling storm of revolution. The Soviet Union emerged from its upheaval as a distorted caricature of socialist ideals. Its present Czar, Leonid Brezhnev, shakes hands with Richard Nixon, abandons North Vietnam to American terror-bombing, and refuses to send aid to Chile after the United States cuts off its support.

Thus has the dialogue been joined--first between Edward Bernstein and Marx's heir, Kautsky, then between Lenin and the western European Social Democrats, continuing to the present day. The dispute has split the Left in countries on every continent and had more than a tangential effect on the course of recent history.

THIS DEBATE has enlarged in importance as the twentieth-century limped along. Originally, Activist socialists thought revolutionary violence would have to be directed only against the old ruling classes, but the horrible birth of fascism in the 1920s and 30s dramatically enlarged the scope of the potential repression. First in Italy, then in Germany, revolutionary upsurges from the Left led to polarization and a counter-revolutionary mass movement from the Right--a lower middle-class army of storm troopers spouting nationalism, order, and the need to repress the nascent lower orders.

Small businessmen, farmers and white-collar workers, clinging to status pretensions that threatened to evaporate in the burning sun of an egalitarian revolution, enlisted in Hitler's and Mussolini's armies, wielding banners inscribed 'honor and duty,' thrusting aside the old conservative classes in their eagerness to dismember the Left.

Revolutionary Activist violence had to take this new development into account. No longer could repression for progress merely be directed against bankers and landowners. There were new potential enemies, masses of them. An Activist revolutionary scenario would have to contain the expected fascist reaction. Now repression might well have to be employed against small farmers and shop-owners and Portuguese peasant soldiers.

Chile in the past few years has re-enacted the scenario of polarization. The old conservative ruling class was rapidly joined in its opposition to the Allende government by a growing fascist movement, which, centered in the Patria Y Libertad (Fatherland and Liberty) movement, drew increasing support from the middle classes. Patria Y Libertad was formed only after Allende's 1970 election, but the group rapidly gained strength, attracting financial support, as had Hitler and Mussolini, from members of the old conservative landed and industrial classes. The last few months of the socialist government were punctuated with terror bombings and assassinations directed against the Left for which the fascists claimed credit.

THESE ARE THE PEOPLE who killed socialism in Chile--the small truck-owners, as well as the big businessmen, the shop-owners as well as the owners of the giant rural estates. They acted as had their predecessors in Italy in 1922 and Germany in 1933--out of fear that their way of life was about to be eradicated. They acted as they had to act. There was no other way short of surrendering their view of the world.

This is the great fallacy underpinning liberal critiques of Popular Unity. The polarization decried in liberal American newspapers and magazines was not somehow a product of Allende's bungling, but an inevitable consequence of the drive toward socialism. 'Going slower,' as The New York Times and others advised, would only have postponed the squaring off. At some point, the truck-owners would have thought Popular Unity was going to take away their trucks. At some point, they would have struck back against socialism.