VIEQUES, Puerto Rico (AP) _ Might or right: It's a decades-old debate on this island of white sand beaches that doubles as the only remaining bombing range in the Atlantic.

``We're living in a war zone,'' complains Gilberto Clark, a nature guide.

The U.S. Navy occupies two-thirds of Vieques, leaving to local residents only the middle strip of this 21- by 4-mile island off Puerto Rico's eastern coast. American troops have used it to prepare for every military engagement since 1941, when the government bought the land for $1.4 million.

Armies and navies from around the world send personnel to train on the eastern end of Vieques, dropping bombs on this hilly outcrop atop coral reefs and conducting other military exercises 235 days a year.

Clark and other residents complain about the booming explosions that sometimes go on for days, shaking the earth like quakes.

On days when dangerous exercises are under way, an orange flag warns civilians to stay clear of the base, which has the best beaches and good fishing spots that are open to the public. In September, a scuba diver suffered from the bends when he was frightened by an underwater explosion and swam to the surface too quickly.

The Navy denies residents' charges that its bombs have destroyed fragile island and marine ecosystems, hurt fishermen's livelihoods and kept tourists away.

Islanders blame the Navy's presence for Vieques' high unemployment, officially around 50 percent.

``This land could be used for factories, or to expand tourist facilities,'' says Luzcelenia Hernandez, a teacher. ``Instead, our island is a military playground, with bombs exploding at our doorsteps.''

Now relations are being further strained by a U.S. government plan to install a radar station on Vieques to help detect drug-smuggling planes. The announcement dashed hopes that an end to the Cold War would mean a Navy pull-out.

Opponents charge the radar poses a cancer threat.

Vice Adm. Diego Hernandez, former chief of the Navy's Caribbean force, denies there are health risks, saying the transmitter will have a mile-wide buffer zone.

That assurance is not enough for the 9,000 islanders already suffering the highest cancer rate in Puerto Rico.

Dr. Rafael Castano, a member of the Committee for the Rescue and Development of Vieques, blames the stress of military activity for the cancer rate of 208 per 100,000 residents. The average for all of Puerto Rico is 120 per 100,000 residents.

Islanders express skepticism about a Navy study that discounts health risks, saying the Navy has lied to them before.

Robert Rabin, president of the Vieques advocacy group, points to the Navy's recent denial that in October 1992 it dropped nearly 20 tons of bombs on Vieques and doused parts of the island with napalm _ even though both actions were reported by the in-house Navy newspaper El Navegante at the time.

Navy officials argue the military has benefited Vieques by preventing harmful development projects from polluting the island.

Lt. Toby de Mier, the Puerto Rican-born officer in charge of the base and its 70 sailors, says Vieques' reefs are among the most pristine in this U.S. commonwealth. ``I snorkel there. I know.''

Juan G. Gonzalez, a professor of marine sciences at the University of Puerto Rico, counters that the bombing practice has torn craters in the surrounding reefs and killed vital marine vegetation.

Despite the resentments, residents usually maintain an uneasy peace with the base personnel, who conspicuous in their military hair cuts and military trucks rarely venture into town.

But on May 11, about 35 fishermen tried to persuade six warships from Belgium and the Netherlands to pull out of Sun Bay, a popular fishing and tourist cove.

The sailors refused, then doused the fishermen with high-pressure fire hoses. Each side hurled tools. The fishermen claim the sailors fired tear gas. Hundreds of European soldiers and sailors were around Vieques at the time, including 1,100 from Germany.

A Navy spokesman, Raul Duany, says such incidents are rare and argues that most Puerto Ricans see the military as an important source of jobs.

Indeed, in the town of Aguadilla on Puerto Rico's main island, residents are lobbying for an abandoned military base to become the new home for Army troops when the U.S. Southern Command leaves Panama.

``The Southern Command is a necessity here,'' says Willie Morales, a vegetable seller in Aguadilla who is hopeful of getting a job.

Residents of Vieques disagree.

``People in this community are willing to do whatever is necessary, including civil disobedience, to defend their right to live without this military craziness,'' says Rabin, surveying the island from atop a 16th century Spanish fort, the legacy of its first colonizers.