Robert Owen is a 1980s version of the all-American boy -- adventurous, athletic, bright and patriotic.

Those who know him say the 32-year-old, 6-foot, 4-inch Owen is a soft-spoken but tough-minded man driven by intense idealism to improve the world, defend the United States and fight communism.

Yet Owen's life also has been undergirded by trauma and, recently, controversy and mystery.

In recent months, Owen's name has been connected with one of President Reagan's most controversial programs: aid to the Nicaraguan contra rebels.

Officially, Owen was a paid consultant to the State Department's Nicaraguan Humanitarian Assistance Office (NHAO). His contract there expired May 28.

But unofficially, according to three administration officials who monitor contra activities and a senior contra official, Owen has been a secret operative acting as liaison between the National Security Council (NSC) and the contras to help skirt a ban on direct involvement in contra military affairs by U.S. officials.

NAMED AS DEFENDANT

Owen's name has come up in allegations of illegal contra activities, including gunrunning and alleged plots to murder dissident rebel leader Eden Pastora, who recently announced he was giving up the armed struggle. Owen is also one of 30 defendants named in a $23.8 million lawsuit filed in Miami federal court two weeks ago blaming the contras and their supporters for the May 30, 1984, bombing of a Pastora news conference in Nicaragua in which eight people were killed and 25 were injured, including Pastora.

Three U.S. officials and the contra consulted for this article said neither Owen nor the rebels were responsible for the bomb.

The four said Owen's main role was as intermediary between a senior NSC official, Marine Lt. Col. Oliver North, and the contras from late 1984 to mid-1985, precisely when Congress banned U.S. involvement with the rebels.

Exposing the arrangement under which North allegedly maintained contact with the rebels is one objective of a congressional investigation expected to begin after the vote later this month on Reagan's request for an additional $100 million in contra aid.

"Ollie handled the contra account at NSC, " one of the U.S. officials said, referring to North. "But since he couldn't deal with the contras directly because of the (Congressional) restriction he needed an operative to allow the administration to continue assisting the contras after all other avenues had been exhausted. That's what Rob Owen did."

North refused comment, but an administration official authorized to speak for him said he "has not been involved in illegal activities." Owen declined to be interviewed.

For Owen, his involvement with the contras seems to have been the culmination of a lifelong desire to leave his mark on the world, to fight communism and to be close to war.

Judi Buckelew, a former White House press aide and Owen's former girlfriend, said Owen was deeply affected by the 1967 death of his older brother Dwight in Vietnam. The event influenced Owen to carry on his brother's ideals and avenge his death by opposing communism, Buckalew said.

LOVE OF COUNTRY

"Whatever Rob did for the contras, he did out of a sense of helping the country, like Dwight would have done, " Buckalew said.

Owen was 13 when his brother was killed in a fire fight between Vietcong guerrillas and South Vietnamese district officials. Dwight was then officially working for the State Department's Agency for International Development, but a source close to the administration said he was actually a CIA agent.