At a time when the late Evita Peron of Argentina is the subject of a Broadway musical, scenarists might well study another ambitious first lady: Imelda Marcos, wife of Philippines President Ferdinand Marcos.

She has created an aura of aloofness and remoteness about herself, is a great performer, strong willed and plays her role flawlessly. From a politically powerful family -- the Romauldezes of Leyte -- she became known as the "Rose of Tacloban" (the capital city of Leyte) at age 18 and represented her native island in the Miss Philippines contest.

Although her family was politically prominent, Imelda Romualdez grew up in a situation that was described as "impoverished" in a biography called "The Untold Story of Imelda Marcos." Both book and author have been banished from the Philippines. The young Imelda even lived for a while in a grage, and was mistreated by a cruel parent, according to this unauthorized biography.

She worked in a music store, singing songs to help sell pianos, and was introduced to an ambitious young congressman named Ferdinand Marcos.

A whirlwind courtship followed, and a personal friend of the Marcoses told my associate Lucette Lagnado that Ferdinand sent Imelda diamonds daily during their brief romance. "I wish he would have courted me longer," she joked.

Once Marcos was elected president, the political heritage of his wife's background was not long in asserting itself. She became governor of greater Manila, and according to some sources was the principal source of Marco's decision to abandon democracy in the fledgling republic and establish a military dictatorship.

According to some sources, Imelda Marcos suffers from an "edifice complex," ordering grandiose public buildings to be constructed in impossibly short order. And there is talk that the Philippines' first lady seriously hopes to succeed him as president if anything should happen to Marcos.

Whatever the future decrees for the first lady, there is no doubt in anyone's mind that she is Marcos' nonpareil ambassador to the world at large. A typical example of her operations abroad was her latest grand tour of the United States. She cultivated the conservative high and mighty, including, as I reported earlier, former president Richard Nixon at an elegant soiree in her hotel suite.

She also took the time to contact her husband's principal political rival, Benigno Aguino, who is living in exile in Cambridge, Mass. The strange part of Imelda Marco's opening to Aquino is that he has been vociferously promoting the overthrow of the Marcos regime. He has even been accused of responsibility for the bombings and other acts of violence that have shaken the Marcos government in recent months.

Yet it appears that Imelda Marcos' latest trip to New York had as its chief purpose a confrontation with Aquino. The top-secret meeting between the Philippines president's wife and his most dangerous opponent lasted 4 1/2 hours.

She pointedly stressed her supposedly personal friendship with Ronald and Nancy Reagan, noting that in 1969 they stayed at the Philippines presidential palace on a visit -- "where friends stay." She also mentioned the party she threw for Nixon, and even played the videotape of Nixon dancing a native Filipino dance and toasting his hostess in lavish terms.

Mrs. Marcos claimed to have had a conversation with President-elect Reagan himself earlier in the week. In any event, the message was clear: with such friends now coming to power in the United States, Marcos didn't have to worry about opposition from the likes of Aquino.

But for all her name-dropping, Imelda Marcos may have betrayed an anxiety that as a politician she would not want to have shown: what really worried her, it turned out, was the thought that anti-Marcos activists -- whether or not Aquino was indeed calling their shots -- might do harm to her son, Ferdinand Jr.

The boy is attending school in this country, and threats have been received by the Marcoses against his life. Imelda repeatedly beseeched Aquino to call off the threats to her son.