Faces stern, ears protruding from near-naked heads under spotless white caps, the 86 young men clicked smartly across the stage here today in Little Hall Auditorium. A three-star general gave each of them a handshake, a diploma and a smiling nod, and they became part of "the best of the finest," a battalion of 1,250 Marine security guards, the last line of defense in American embassies around the world.

As the graduates filed by, the media's glaring kleig lights sparkling off their shiny black shoes, the nine special guests from Detachment Tehran couldn't help but flash back, if only for a moment. They had been there before.

"I watch these guys go up and go down and I remembered when I graduated myself," said Sgt. Steven Kirtley, a hostage in Iran for 444 days and a member of the Marine Security Guard School, class of 1979.

"I think attitudes have changed as far as the importance of Marine security guards goes," he said.

Ten years ago, an assignment with MSG Battalion was seen by young volunteers as a chance to grab for a glamorous Marine Corps billet: they would sign up to walk a little guard duty in exchange for passage into the fairytale life of limousines, diplomats and embassy balls. It was a benefit, a good deal. See the world, no strings attached.

Then came the 1970s, a time the directors of the school here call the Decade of Terrorism, when Marines faced "direct contact with terrorist forces" in such far flung hot spots as Buenos Aires, Beirut, Nicosia, San Salvador, Managua, Tehran and Islamabad.

For the first time, said school operations officer Maj. Allen Guins, 'MSG's confronted hostile forces face-to-face." They used "mace, tear gas and, on rare occasions, live fire to hold their positions against armed attacks. Despite the fact that the host government is responsible for the protection of the embassy and U.S. personnel, more and more of this role has fallen on the Marines. We are up to the challenge."

Facing this challenge in their typical rough-riding, leatherneck style, the Marines have recently dedicated Marshall Hall, a $3 million mock-up of an embassy complete with bullet-proof glass, video monitors and doors that can be locked instantly from a central post.

And now, aside from teaching the volunteers how to make security sweeps of trash cans and desk drawers and holding bomb drills in the middle of the night -- using dummy lunch bags or suitcases armed with alarm clocks -- the instructors have added a whole host of new, Tehran-inspired lessons.

Last week, about 100 Marines were recruited to simulate a riot. They stormed Marshall Hall armed with water balloons, eggs, rotten tomatoes and even a dummy that they burned in effigy. They chanted for American pigs to go home. This time, however, the guards won, Guins said, even though they had to do all the cleaning up afterward.

At other times, Guins said, "We bring in nice-looking young ladies and have them try to finesse their way into the embassy . . . The MSG students go through the gauntlet."

As in the past, the embassy guard volunteers -- some 500 spread through five classes a year -- receive training in physical fitness; the use of "deadly force weapons" such as .38-caliber pistols, Uzi submachine guns, Remington pump shotguns and nightsticks; and civivlian dress (illustrated in a training slide by a young Marine in three-piece polyester splendor, the collar of his pink shirt somewhat askew).

Today's training is augmented by courses in espionage and terrorist activities, evasive driving and counterintelligence. And, "we make them aware that they can become a hostage just like that," said Guins, snapping his fingers and taking another sip of the sweet coffee he picked up on a recent trip to Colombia.

Drawing on studies of the Patti Hearst kidnaping case, the Marines are acquainted with the possibility that they may come to identify with their captors, and they are familiarized with rescue operations such as the Entebbe raid.

"We teach them not to establish a pattern in their lives so they won't get kidnaped," Guins said, "and that if taken hostage, to remember that the Marine Code of Conduct is in effect at all times. In a hostage situation, survival is of primary importance and maintaining their dignity will enhance their chances of survival."

But the trump is something Marines soak up by being Marines, said Guins, a 19-year veteran with a drawl spun down home in Boyce, La., and with three tours of Vietnam behind him. The most important lesson is not something that can be taught in a few hours of a few weeks. "Making It" is a state of mind to Marines, a macho grunt pride symbolied by shaved heads and pushups 4 p.m.

"I worry about each and every one of my men," Guins said. "Who knows? Ottawa, Canada, could become a hostile fire zone tomorrow. But these men are Marines. They accept the fact that yeah, I may get shot, I may have to return fire. I don't think you'll find a Marine alive who is afraid. hBut they're not afraid to have fear, either. You may get killed, that's a fact of life. You're mentally prepared to accept that, even though it's hard for me to convince my wife."

Meanwhile, the graduation ceremonies over, the new guards sampled coffee and doughnuts in Marshall Hall and mingled with the members of Detachment Tehran. Cpl. Jack Jusino, bound for Islamabad, Pakistan, was wide-eyed after asking former hostage Sgt. Rodney Sickmann for his autograph.

"He's a real hero," said Jusino. "He's one of the reasons I signed up. I feel real pride and patriotism."

Would Jusino be able to handle being a hostage for 444 days like his idols?

"I'm man enough to take it," said the 19-year-old.