A By Carol J. Williams and Sam Howe Verhovek

BOARD THE USS IWO JIMA – This 844-foot-long amphibious assault ship was coursing over choppy waters 40 miles off the North Carolina coast when a sudden warning – “Missile incoming, starboard side” – roared through its cavernous entrails.

It was a nocturnal war drill the ship’s 1,500 sailors had been through many times before. Alarms clanged, orders were shouted, sailors manned gun turrets on the misty deck, and dozens of firefighters sprang into action.

But this time, the ship’s crew was operating under the gaze not just of the ship’s commanders but of 58 journalists, notebooks in hand and cameras rolling.

In an unusual experiment launched over the weekend by the Pentagon, reporters, photographers and camera operators from 31 news organizations are spending a week with the military in potential combat situations. It is an exercise that defense officials describe as an important part of their contingency planning for media access to military operations if the United States makes good on threats to invade Iraq.

Aside from drills aboard the Iwo Jima, the reporters, including one from the Russian news agency Itar-Tass and another from the United Arab Emirates, will visit the Marine Corps base at Quantico, Va. Among the matters to be covered there, Pentagon officials say, are reactions to direct and indirect fire; protection against nuclear, biological and chemical attack; identifying mine hazards; an overnight march with 25-pound backpacks; and boarding a helicopter with war gear.

Pledging to improve on what has become an adversarial relationship with the news media in times of hazard, the Pentagon is running the “media boot camp” this week to expose journalists to the rigors of wartime defense. Mock drills involving missile hits and enemy encounters are designed to show reporters the complex interaction of sea operations and front-line maneuvers, purportedly in anticipation of media accompaniment of troops headed for the threatened Persian Gulf confrontation.

“We’re trying very, very hard to raise the comfort level of the media and the military. We’re trying to make it better,” Pentagon spokeswoman Victoria Clarke told reporters gathered for the first of four planned media-military training sessions. The rank and file clearly reveled in the extraordinary attention being paid to their unsung roles in the looming war’s run-up.

“I’m glad the media’s here. I want people to know exactly what we’re capable of, how hard we work,” said 21-year-old Dave Richards, a gunner’s mate third class from Jackson, N.J. “Our preparation is 24/7. One minute you’re in your rack, sound asleep. The next thing you know all hell’s breaking loose – even if it’s only a drill.”

It was just such a test that exposed this troop-deploying craft to a mock missile attack Saturday night – a scenario that included a botched interception effort to give damage-control crews some practice.

The exercise was eerily reminiscent of the October 2000 terrorist attack on the U.S. destroyer Cole off Yemen. A small boat approaches with unclear intentions, ignoring efforts at radio contact and warnings to turn around or confront live fire.

Such noncompliance prompts deployment of the Iwo Jima’s 30-foot inflatable launch to observe and engage the potentially hostile craft. That involves bearing down on the intruding vessel to prevent it from attacking the $1 billion Iwo Jima and its priceless human cargo.

“It’s my job to protect the ship, and I have to look at it as a cost-benefit analysis. It can be me and two or three other people who get killed or me and 2,000 people. It’s a greater-good situation. I have to look at it that way,” said John Obrien of Lima, N.Y., a boatswain’s mate first class.

A 29-year-old human shield between the ship and its suspected enemy, Obrien would be expected to deflect the approaching vessel or die trying.

“There’s always been that danger. I think I’m just more aware of it now,” Obrien said. “There’s always that feeling that `It can’t happen to me,’ but the Cole incident brought to the forefront that it can.”

Service members preparing for their first extended sea duty on this ship, expected to be at sea six to seven months next year, confessed to mixed emotions about confronting danger and proving their mettle under fire.

“I’m kind of nervous from all the biological and chemical weapons drills, but I’m also looking forward to it,” said Luke Warner of Chicago, a damage controlman second class.

Communication with his fretful grandmother and girlfriend via e-mail could be restricted if the crew is compelled to observe “electronic silence” during operations in what could by then be a war theater.

Although U.S. forces from deckhands to the commander in chief recite a single mantra – that these shipboard drills are purely theoretical and no actual war moves are in the making so far – they readily concede that a confrontation with Iraq is what’s in their preparatory cross hairs.

“You have to figure what will be your most likely scenario and prepare for it. That only makes sense,” said Lt. j.g. Christine Komoroski, an engineering officer.

If the week’s worth of training is designed to raise comfort levels on both sides, it is not completely designed to make the media comfortable. Wake-up calls, for instance, were clearly much earlier than some reporters were accustomed to.

“If you have an alarm clock, don’t worry about setting it. We’ll wake you up,” said Komoroski, who dutifully knocked on stateroom doors at 5:30 a.m.