Washington — In choosing a moderate coalition to lead their new parliamentary government, voters of the Caribbean island nation of Grenada have laid a strong base for continued aid from the United States and attraction of foreign investment. In a country where as much as one-third of the labor force has been unemployed, such economic help is considered vital.
''This is a positive development - as good a first step as they could have made,'' says William Perry, an expert on Latin American elections with Georgetown University's Center for Strategic and International Studies.
The New National Party, a coalition of three moderate parties launched last August with the help of the US, a number of top leaders from other eastern Caribbean islands, and local business and religious leaders, won more than a two-thirds majority in Grenada's new parliament.
The election result is widely viewed as a vote for stability and continuation of US aid, which will total $57.2 million during the two years through fiscal 1985, and for stepped-up investment from private sources in the US and other countries. It is hoped that in time Grenada, which mainly produces bananas and nutmeg for export, will be able to diversify its largely agricultural economy. Grenadans would like to add to their export mix seafood and electronic assembly parts.
It has been 13 months since American troops descended on the tiny island where leftist leader Maurice Bishop and several of his top aides had been killed by a rival Marxist faction. There still are 250 US Army troops on the island, but they are expected to leave early next year, after Grenada's new police force completes its training.
A public opinion poll taken among some of Grenada's 48,000 voters earlier this year showed a strong majority feeling there was no good leader they could trust in the country or wanted to see as prime minister. But by their vote this week Grenadans have given the nod to Herbert Blaize, a self-effacing lawyer from the dependency island of Carriaucou who headed the island government for five years in the 1960s as chief minister. He is respected for his integrity and fiscal conservatism but is not particularly known for his popular appeal.
In that respect, Dr. Perry says, the vote was somewhat unusual for a developing country where charismatic, authoritarian leadership is often the norm. ''This was a vote for a system rather than a person,'' he says. ''In a democracy, you're voting for a process, and you get accustomed to voting for dull leaders - they're safer.''
In Monday's election, Grenadan voters rejected what Perry calls ''the ridiculous extremes.'' On the left, getting virtually no support, was the Maurice Bishop Patriotic Movement, including most of the remnants of the New Jewel Movement, which ruled after overthrowing Prime Minister Eric Gairy in 1979 .
Mr. Gairy, mystical leader the right-wing Grenada United Labor Party, once urged the United Nations to investigate unidentified flying objects (UFOs). He returned to the island from exile three months after the US ''rescue mission.'' A former trade unionist who had dispensed considerable patronage during his more than 20 years of leadership, Gairy had the advantage of being well-known commodity, despite his somewhat negative rating among many voters. In this election he opted not to put himself personally on the ballot and campaigned as a champion of US policy, favoring both a permanent American military presence on the island and a British naval base.
Early reports indicated the United Labor Party had won only a small fraction of the available council seats.