Socialists Take the Helm in Jamaica. Manley hopes to strengthen US ties by aiding war on drugs. NEW PREMIER ... NEW POLICIES?

FORMER Prime Minister Michael Manley was sworn into that office again yesterday, ending eight years of conservative government on this Caribbean island. A socialist intellectual whose close ties to Cuba worried American policymakers in the 1970s, Mr. Manley now says he looks forward to being a close ally of President George Bush in the fight against drug trafficking in the region.

Manley's socialist People's National Party (PNP) won a landslide victory over the conservative Jamaica Labour Party government of Edward Seaga. Jamaicans gave the PNP 57 percent of the vote and 46 seats in the island's 60-seat Parliament.

Mr. Seaga, a darling of the Reagan administration credited with restoring the island's troubled economy by infusing a strong dose of capitalism, stoically conceded defeat although his party has demanded recounts in several close races.

Seaga had defeated Manley in 1980 in a bitter election accompanied by street violence that left hundreds dead. He was easily reelected in 1983 when Manley's PNP boycotted a snap election in a dispute over voter registration.

Both men were seeking an unprecedented third term in the volatile island of 2.4 million, where party loyalties are so fierce that opponents often take to the streets with guns to fight out their differences. Over a dozen people were killed in the most recent election, but party leaders said the campaign was relatively calm. Seaga and Manley had signed a peace accord in August and the state-run radio and television stations repeatedly aired songs by the late Jamaican superstar Bob Marley and videos promoting peace.

Polls before the vote indicated that while most people conceded many of Seaga's tough fiscal policies had worked, they believed social services had suffered and disliked the tone of his government, which was often secretive.

Manley, on the other hand, had promised to ``put people first'' and listen to the views of all.

``It's traditional to chuck out the government every two terms anyway,'' said sociologist Douglas Manley, the new prime minister's older brother and a newly elected member of Parliament. ``But Seaga's personal style, which is very aloof and autocratic, made him come across as callous.''

Manley has admitted he made mistakes during his two terms in office from 1972 to 1980 and even praised some of Seaga's successful programs, which he says he will continue.

Manley said at a press conference following his victory that he was planning a trip to Washington to meet with Bush and key congressional leaders as well as officials from the Drug Enforcement Agency. He said that, while the United States government and his own may have some philosophic differences, they were both committed to democracy, due process, an end to the drug trade, and the ``right to make a profit.''

His statements were a departure from the 1970s, when he vowed to dismantle capitalism in his country ``brick by brick.''

Manley's appeal has always reached beyond the shores of his tiny nation and he has often been considered a leader in the third world. On Friday, Manley talked of building a ``nonconfrontational'' alliance of developing countries on the issue of third-world debt.

Jamaica has an estimated $4.5 billion debt that makes it one of the most indebted nations per capita in the world. Almost 50 cents out of every dollar Jamaica earns goes to pay off its loans.

Manley said he ``would not in any circumstances walk away from debt.'' But he said an alliance of third-world nations might find ``a common position ... that makes sense.''

Many have suggested that while Manley has changed on the surface, he is still committed to making Jamaica, a socialist state closely aligned with Cuba.

``My answer to that is what I say and what I do,'' Manley said.

The United States and Jamaica's neighboring islands are apparently prepared to give him the benefit of the doubt.

``He has clearly stated he wants good relations with the United States and we share that objective,'' State Department spokesman Charles Redman said after Manley's election.