Sour US note on the Horn

Like the Carter administration before it, the Reagan administration has been unable to meet the challenge of devising a constructive policy toward the Horn of Africa, a policy that would reflect America's consistent interest in human rights, economic development, and settlement of conflict by peaceful means.

The recent rushing of plane loads of arms to Somalia betrays the lack of any real policy toward this strategically important area. It can only postpone, not prevent, further deterioration of Somali President Siad Barre's already weak hold on power. It exacerbates relations with Ethiopia and bolsters the worst element in Chairmen Mengistu's poorly consolidated government.

More than $3.5 billion worth of arms have been poured into the Horn during the past 20 years, while economic development in the region slowed and has now practically come to a halt.

Most of these arms were supplied by the Soviet Union. The Russians gave the Somalis $600 million worth of weaponry with which they prepared their attack on Ethiopia in 1977. The Ethiopians then needed more than $2 billion in Soviet arms and 20,000 Cubans to fight the Somalis to a draw - but the conflict has never, in reality, ended. The price seemed worth it to the Russians, because they gained preeminence in Ethiopia and a grip on the whole Horn, an area Russia had coveted since the late nineteenth century.

The American contribution to arming the Horn was modest - less than $300 million during the entire 25 years of military relationship with Ethiopia. Some difference in Somalia now. But why go on playing arms supplier at all, in any quantity? The last thing this part of the world needs is more weapons.

To prop up Siad Barre simply because he broke with the Soviets and is opposed to Mengistu's Marxist regime in Ethiopia makes no sense. Siad may well be a better Marxist than Mengistu. He built a Soviet-style client state in Somalia much faster than Mengistu has done in Ethiopia, complete with Socialist party and pervasive police apparatus - neither of which has been disbanded since he expelled the Russian military. Siad's system is as far from democracy as any in Africa. Somalia's state-managed economy is a shambles.

The country exists on the ''profits'' from the miserable Ogaden refugees, at least 650,000 of them, who are confined in camps, discouraged from either returning home or resettling in Somalia, while the Somali government skims off between a third and a half of all the food and medical aid that well-meaning US and European governments and private relief agencies provide. The US government spent nearly $300 million of the taxpayers' money during the last four years on refugee aid in the Horn!

Siad recently dismissed a sizable proportion of his cabinet members and had reportedly imprisoned some of them. As opposition grows, he fills government posts from a narrowing group of tribal cronies and the effectiveness of an already corrupt and inefficient administrative apparatus declines further.

If Somali bases are important to the United States, elementary wisdom leads to the conclusion that we work to get a more effective and viable government in the country and one that does not continually conspire to lure us into backing its aggression against Ethiopia. At a minimum, whether we do anything else at all, we should be maintaining distance from Siad so that his fall is not seen as a defeat for the US - which certainly need not be the case.

The Somali Democratic Salvation Front (SDSF), which has emerged during the past year as the foremost among the several groups of anti-Siad Somalis, enjoys Ethiopian support and may be getting money from Qaddafi.

Nevertheless, opposition inside Somalia is too widespread to justify the conclusion that these people want to remain tools of Ethiopia and Libya.

What has been going on in Somalia in recent weeks is still obscure, but if the SDSF is receiving logistic support from the Ethiopian military, it is merely a belated imitation of the kind of operation Siad Barre - originally with Soviet and Cuban support - has been mounting against Ethiopia since the mid-1970s.

Continued tension in the region works to keep oppressive regimes in power in both Ethiopia and Somalia. It causes unneeded strain for the other countries in the region - Sudan, Kenya, Djibouti - which are trying to build a better life for their people. Only Soviet interests are served by continued tension and recurrent crisis.

American interests would be served by new initiatives to break the vicious cycle of provocation and exaggerated response. Through Kissinger, Vance, Muskie, and Haig, the US has lost ground in the Horn region and based its actions on pretense and illusion. It is not too late to try a more creative approach which would have as its ultimate aim the liberation of the whole region from strife and Soviet interference.

George Shultz will have nothing to lose by trying a new course.