It is April 18, 1983, and I am visiting the American Embassy in Beirut as a reporter for the Wall Street Journal.

It is a coolish morning, a day to wear the winter-weight suit one last time. By the time I reach the embassy, a bright sun is beginning to cut the haze. Approaching the front entrance on the Corniche, grand and all but unguarded, I look across the shimmering Bay of Beirut to the slopes of Mount Lebanon, where there is still a trace of snow at the peak.

The moist, sweet air of Lebanon is on my face like a phantom kiss.

The good times are returning, I think. The city has been pounded by eight years of civil war, and then by the Israeli invasion, and then by the massacre of Palestinians at Sabra and Shatila. But now the United States has arrived as Lebanon's protector; U.S. Marines are at the airport in what the embassy calls a "presence mission."

My appointment is at the Office of Military Cooperation on the fifth floor. The Army officer who meets me there has an upbeat message: The United States is rebuilding the Lebanese army into a force for national reconciliation that will bring together Sunnis, Shiites and Christians. The officers are wearing real boots now, he says, not those Gucci slip-ons like in the old days.

I take notes as the Army officer talks. It's almost believable, what he says. You want to think we understand what we are doing in this country -- that those Marines really are as popular in the Shiite slums out by the airport as their officers keep telling me when I go on patrol with them . . . and see the wary, watchful eyes in the shadows.

My appointment ends around 12:30 p.m. Rebecca McCullough, the Office of Military Cooperation's administrative assistant, takes me back down to the lobby. She's wearing a summer blouse and a winter skirt, caught in between the seasons on this April day.

I pick up my passport from the Marine guard manning Post No. 1 behind a thick plexiglass screen -- shiny brass buttons, forbidding Marine physique. I climb the hill back to my hotel, wondering if there's a story in what the embassy official has told me.

At 1:03, I hear an enormous blast. The percussive force shakes my windows, nearly a mile away. I have a momentary feeling of vertigo, like fear but worse. I run back toward the Corniche.

When I reach the building, Marines are trying to form a perimeter. I look up at the remains of the embassy: The center facade has collapsed; rooms have been sheared in half; a body is visible, hideously, on an upper floor.

Sixty-three people are dead, including 17 Americans. It's the deadliest attack ever on a U.S. diplomatic mission up to that point. It takes many years to confirm that it was an Iranian operation, organized by operatives from their Revolutionary Guard.

Nobody understands it that day, but a new kind of war has begun.