An old, yellowed and dirty, but unused postcard found in a dingy Massawa shop last month probably explains more about Ethiopia than many a scholarly tome.

The card, more than 45 years old, is from the 1935-1941 Italian occupation era in Ethiopia when Mussolini tried to make Italy a colonial Power.

Historically, the postcard is a period piece. As a piece of propaganda, it is revealing.

The card shows scores of Ethiopians clapping their hands on a hillside in the Tigrean town of Adigrat in northern Ethiopia. The Italian caption says: "Adigrat -- the indigenous people acclaim the Italian occupation troops."

Most of the people pictured are surely dead now, since even today the average life expectancy in Ethiopia is only about 40 years.

The few who may have survived undoubtedly stood in the same place and applauded the British troops who liberated Ethiopia from fascist rule. Surely they had many occasions to applaud emperor Haile Selassie, who returned to his country and throne in 1941 to reign for another 33 years. Now, they most certainly would applaud Chairman Mengistu Haile-Mariam, leader of Ethiopia's Marxist, military government.

The card from "Italian East Africa" shows that Ethiopians, like most people, know how to live with their rulers, whether they are left, right, feudal, capitalist or Marxist.

Some of the same journalists who used to heap praise on the emperor now do the same for Mengistu. The Marxist rhetoric is often shrill in comparison to the awesome accolades devoted to Haile Selassie, but the significance is probably about the same.

EVEN THOUGH ETHIOPIA is an ally of the Soviet Union, Cuba and Libya, some recent events point up problematical aspects of the relationship.

Last September two Russians, believed to be military men in civilian clothes, were shot to death on their neighborhood street. There was no publicity about the incident, and little is known about it.

The U.S. Embassy has weathered a difficult period during which it housed two Cuban soldiers who sought asylum.

Both have now left the embassy, but the Ethiopian government denies knowledge of their whereabouts and continues to hold the United States responsible for them.

One was picked up for violating the midnight curfew when he slipped out of the embassy for some Christmas merriment a year ago. The other fled after an altercation with a Marine guard.

As for the Libyans, Chairman Mengistu showed in October that there is a limit to his loyalty when he signed the Egyptian Embassy condolence book for the assassinated president Anwar Sadat. Sadat was the archenemy of Libyan leader Muammar Qaddafi.

ETHIOPIANS HAVE learned to cope with "the change," as the uncommitted often call the revolution, in a variety of ways.

One official who used to travel with the emperor on all his overseas trips suddenly discovered a long-lost membership card in a foreign communist party.

Another, however, seems to be out of step, at least considering the symbols in his life.

In the old, imperialist days he was a representative of an East European firm and drove a Soviet "people's" car. Nowadays, he has left his government employment and runs a private firm, is the representative of a British company, and drives a Peugeot 504, a much sought-after status symbol in Africa.

SOME HABITS took several years to change, according to persons familiar with the early days of the revolution.

So entwined was the image of the emperor in the lives of Ethiopians that most used to swear on his name -- saying Haile Selassie munt to emphasize that what they were saying was true.

It reportedly even took several years before the exclamation Haile Selassie munt disappeared from meetings of the Dergue, the revolutionary ruling body in Ethiopia's military government.

MARXISM OR feudalism, pro-East or pro-West, some things undoubtedly will never change in this ancient country.

One is the penchant for speaking obliquely. Rarely will Ethiopians say something directly if they can say it indirectly.

An informal, but sensitive, conversation with an American-educated official ended abruptly when I started to say: "One thing that hasn't changed is..." The woman finished the sentence -- and the interview -- by saying "the ambiguity."

Another constant is the belief of many Ethiopians that they are not Africans, because of the Hamitic and Semitic influences in their past.

In the 1950s, a foreign instructor was even reprimanded for teaching his high school students that they were Africans.

Haile Selassie attempted to change all that in the early 1960s, when, in his quest for international glory, he persuaded the Organization of African Unity to establish its headquarters in Addis Ababa.

Overnight Ethiopians became Africans, but there is evidence that the switch did not stick.

When asking an Ethiopian official about a mutual acquaintance, I made a mistake in spelling the name, giving it the "Mb" beginning typical of southern Africa.

The official blurted out: "That's not an Ethiopian name. That's an African name."

A Western diplomat humorously noted another change.

"In the old days" under the emperor, he said, when a diplomat presented his credentials at the glittering palace hall, he had to "walk out backwards, keeping his eyes fixed on Haile Selassie and always fearful of tripping over one of the emperor's pet lions."

With the monarchy abolished, Ethiopa has joined the rest of the world. Diplomats just turn away and exit after presenting credentials and there are no lions amid the retinue.