AFTER a 15-year experiment with revolution and Marxism-Leninism, Ethiopia - Africa's oldest nation and its second most populous - is today on the brink of disaster. Famine, which may have killed a million Ethiopians in 1984 and 1985, threatens again this year. And civil war in Eritrea and Tigre, the country's northern provinces, now threatens the very integrity of the Ethiopian state. Over the last two years, Eritrean and Tigrean guerrillas have inflicted spectacular defeats on the Ethiopian Army. In March 1988, a month after President Mengistu Haile Mariam executed a general who told him the Eritrean problem could not be solved by military means, Eritrean forces destroyed an Ethiopian force of more than 20,000. In February 1989, Eritrean and Tigrean guerrillas put to rout an even larger Ethiopian army.
As a result, Mr. Mengistu's government had to abandon the entire province of Tigre and give up its last overland link with Eritrea. In August and September Tigrean forces pushed southward, shattering demoralized Ethiopian army units along the way. They now stand within striking distance of Addis Ababa's lifeline highway to the Red Sea port of Assab and less than 200 miles from the capital itself.
Mengistu, who in 1984 set up a Marxist-Leninist party and in 1987 declared Ethiopia a ``People's Democratic Republic,'' is now trying desperately to rally support. Purges he carried out after a coup attempt in May - the first ever against his regime - have left his army seriously weakened. Observers in Addis Ababa think his fall is only a matter of time.
Mengistu's passing will not be mourned in Washington. In 1977, after shooting a dozen or so of his associates, Mengistu threw the US out and delivered Ethiopia, in body if not in soul, to the Soviet camp. For years thereafter he regularly vilified the United States in his speeches, and his government became the bane of American policy in the Horn of Africa. His regime has ruthlessly arrested, tortured, or killed all who opposed it.
Recently, in the face of waning Soviet support, Mengistu has taken to courting the US. Earlier this year he agreed to let former President Jimmy Carter host negotiations between his government and the Eritrean People's Liberation Front. Talks held in Atlanta in September bogged down over procedural issues. Another session was held in Nairobi last month, but so far only procedural issues have been discussed.
Mengistu inherited the Eritrean war from Haile Selassie. But instead of trying to negotiate a solution when that still might have been possible, he plunged his country into a vain and increasingly costly effort to suppress Eritrean resistance. To do this he imposed on Ethiopia - counted by the UN as one of the world's six poorest countries - the burden of an army of over 300,000. Staggering losses - tens of thousands of soldiers killed and wounded each year over the past decade - have caused disillusionment and disaffection at home and finally have discouraged even his Soviet backers.
For years the Soviets provided Mengistu hundreds of millions of dollars in arms. Now they have told him they will fulfill their arms supply contract through its expiration in 1991, but nothing is guaranteed after that. Earlier this year Soviet journals harshly criticized Mengistu's handling of the war and the economy.
Famine is Mengistu's other legacy. The famine of 1984-85 was triggered by drought, but Western experts agree that the underlying cause was the government's dogmatically misguided agricultural policies. The data tell the story. From 1979 to 1987, Ethiopia's annual food production fell by over 2 million tons - from approximately 7.5 million in 1979 to 5.3 million in 1987 - while population grew at an annual rate of 2.9 percent. The regime poured money into state farms and collectivization while forcing the peasant farmer to sell his crops to the state at prices far below any reasonable return on cost or labor. As a result, Ethiopia now depends on Western food donations and even with these is unable to avert chronic famine.
Rather than recognizing his mistakes and trying to correct them, Mengistu launched programs that compounded Ethiopia's disaster. In 1984 he ordered massive relocation of people from drought- and insurgency-affected northern highland areas to the lowlands of southern and western Ethiopia. Some 600,000 were forcibly moved under atrocious conditions; tens of thousands died of hunger, exposure, and disease before international outcry forced a halt to the program.
In 1985, Mengistu's regime began ordering peasants to tear down their homes and move to centralized new villages where they could be more easily controlled and readied for collectivization. More than 8 million have been ``villagized'' since then.
Eritrean nationalists are now closer to victory than at any time since 1977, and the breakaway of the northern province is a possibility that cannot be discounted. And Ethiopians face the ominous prospect of a chaotic and bloody struggle over succession to Mengistu.
There is probably little Washington can do to affect the outcome, but if those who come next have learned the lesson of Mengistu's tragic mistakes and are willing to try to set things right, the United States should be ready to help them.