THE SOVIET INVASION of Afghanistan ranks as one of the most cynical and brutal violations of sovereignty in recent years. To aid Afghan insurgents fighting Soviet aggression and to prevent the repetition of such aggression elsewhere, the United States must take strong measures including arming Afghan rebels and Pakistan to raise the cost of invasion for the Soviet Union to prohibitive levels.

While the economic measures that President Carter has ordered represent a necessary first step in expressing our outrage to the Soviet Union, they alone will be completely ineffectual in blocking the spread of war. The partial grain embargo will only inconvenience the Soviet society. And in the short run, Soviet stockpiles of grain will further cushion the blow. The technology blockade will have even less effect. The United States is the Soviet Union's supplier of last resort for all high technology and currently does less than one quarter of the trade that Japan, the Soviet Union's leading western trade partner, does annually.

Such measures are wonderful ways to express our discontent with the way the world works, but they offer small and non-aligned nations no security and ultimately no guarantee that either big power will ever eschew the use of military force to overthrow legitimate governments.

It would be nice to believe that measures producing largely symbolic impact will impress the Soviet Union enough to block further aggression, will reassure non-aligned nations that their territorial integrity is taken seriously. But the end result--a successful and largely cost-free Soviet annexation of another nation--will destroy any of the long range hopes for peace that proponents of economic measures alone may hope to gain. Instead of encouraging peace, such an outcome will highlight the benefits of war. While it is imperative that the U.S. must not force a cold war, us-against-them military confrontation, it is equally vital that the U.S. be willing to offer the means of self-defense to nations threatened by Soviet expansionism. In this crisis, the U.S. should respond to requests supported by a broad range of odd international bedfellows by Pakistan and, most importantly, by the Afghan resistance fighters.

It is clearly inappropriate at this time to engage in strategic arms sabre rattling or to expand dramatically the U.S. military establishment; neither foreign policy gains nor military advantage can be garnered in this way. However, cooperation on such matters as SALT is essential and should continue, but detente as a whole becomes a dead letter if the fruit of the policy is such actions as the Afghanistan invasion. Similarly, direct U.S. military intervention is wholly inappropriate; the U.S. must preserve the distinction between itself and the U.S.S.R. and avoid the use of its own military forces to destroy a nation.

The Soviet Union has clearly demonstrated that its claims to be the "defender of the third world" are tripe. The U.S. should demonstrate that its "concern" will be translated into real benefits and genuine support for Afghanistan and other potentially threatened nations.