Newport, R.I. — The lieutenant colonel's voice was hard and flat as he told about it: A squad of his marines had infiltrated Syrian lines to set up an artillery spotting post in the Lebanese hills. One of the American television networks found out about it and reported not only the fact but the location on the evening news. The marines made it back safely, but the experience left their officer with a bad feeling about the press, a ''knot in the stomach,'' as he put it.
''Those young men were under my command and their lives were at stake,'' he said.
Not long afterward, a well-respected Pentagon reporter began checking the Navy Department's assertions that new ships were being completed under cost and ahead of schedule. Even though the claims were apparently true - in fact, it was going to be a ''good news'' story for the Defense Department in a major national publication - it took the Navy two full months to provide the reporter with all the facts and an admiral to talk about them.
It left the newsman frustrated and wondering what kind of response he would have had from the Navy if the story had turned out less favorable.
Relations between the military and the news media hit a post-Vietnam low point with the barring of the press from the United States invasion of Grenada a year ago. Since then, both of these elite and powerful institutions have been struggling to attain some sense of cooperation.
While their symbiotic relationship will necessarily remain somewhat combative , there are tentative signs that better understanding on both sides is beginning to help smooth some of the rough spots.
This was evident recently at an intense and illuminating two-day encounter between warriors and news people. It was held at the Naval War College here, and the rules of engagement were that it be ''not for attribution.'' This means that , in the interest of keeping the exchanges lively and direct (as well as protecting careers), no one could be quoted by name.
Among the several hundred mid-grade officers who took part, the general feeling about dealing with the press was summed up by one Army intelligence officer: ''Every time I've had an encounter with the press, it's been a zero-sum game. The best I can do is break even.'' A Navy commander called it ''a no-win situation.''
Another officer with many years' service described the hundreds of newsmen and women who flocked to Grenada as ''a gaggle of ragamuffins. . . . The first place you wanted to take them was the decontamination chamber before you exposed them to the troops.''
Such harsh judgments have their genesis in Vietnam, where most of the officers were young lieutenants and captains, the ''grunts'' leading even younger troops. ''We never got a square deal from the press in Vietnam,'' said a former squadron commander. ''I never once saw on TV the GIs building schools and hospitals.''
There is no doubt that television has drastically changed the nature of war reporting, with its unfiltered and graphic portrayal of death and destruction as well as the immediacy of transmission. ''We worry a great deal about direct broadcasting by satellite,'' a senior Pentagon civilian said.
Another key difference separating today's reporting from that of Ernie Pyle and others during World War II (when reporters wore uniforms and censorhip was not challenged) is that both sides of a war are now reported. Gone are the days when American reporters could satisfy themselves with being (as a senior naval officer put it) ''cheerleaders'' for the US position.
Also, conflicts in the nuclear age are less likely to be clear cut, ''us versus them'' encounters in which all-out national effort is required. Instead, it is agreed, military engagements - if they include direct combat at all and not just ''presence'' missions as in Lebanon - will involve ''low-intensity conflict,'' counterterrorism, and other, more controversial actions.
Among reporters who regularly cover military affairs, the chief complaint is that the cloak of ''national security'' is too often thrown over information that could legitimately be reported. ''It has been so overused and abused,'' said a Pentagon reporter. ''It's seen used to cover up mistakes and drummed out all the time for trivial reasons.''
''As much as we hide behind national security, you hide behind the people's right to know,'' retorted an officer. ''Are you serving people by being their peeping Tom?''
In his lawsuit against the CBS network, Gen. William Westmoreland has complained that unfavorable reporting undermined morale and hurt US military efforts in Vietnam. Yet a participant in the Naval War College symposium who was a US military spokesman in Vietnam said that in no more than a handful of instances did reporters violate the ground rules for combat reporting. And some of the most respected scholars on the Vietnam war (such as Col. Harry Summers at the Army War College) do not believe that the press ''lost'' Vietnam.
Many field-grade officers here might not have agreed, but some senior officers defended an essentially uncontrolled (if sometimes unruly) press. ''I'd much rather have an editor decide what freedom of the press is than some government agency,'' a Navy commodore said.
Among professional public-affairs officers at the Pentagon and among the uniformed services there is also the recognition that the press is essential to the military as a means of winning public and political support for programs and policies.
''You can win the battle but lose the war if you don't have public support,'' said a senior Pentagon spokesman. ''We ask for $300 billion (in annual Defense Department spending), and we have to be able to explain how that money is being spent.''
There was also the acknowledgment by senior defense officials and some uniformed officers at the Newport encounter that reporters should have been allowed to accompany the first US military units that took part in the invasion of Grenada. For this reason, press pool arrangements are being worked out for future operations.
David Gergin, the one Newport symposium participant who spoke on the record, said he sensed an end to the ''Vietnam syndrome,'' including a new generation of reporters and military officers as well as a renewed expression of patriotism in the country.
''There is a real opportunity for everybody - the press and the military - to take a fresh look at these institutions,'' said Mr. Gergen, the former White House communications director, ''to get out of stereotyping each other, to sit down and talk constructively.''
''A little humility is in order on both sides,'' Russell Dougherty, editor and publisher of Air Force Magazine and a retired general, wrote recently in an editorial. ''The military needs the press. There is no other way to keep the public informed.
''Similarly, reporters must realize that freedom - of the press and otherwise - depends ultimately on a strong defense that keeps the nation secure.''