We were watching the Japanese surprise attack on Pearl Harbour as reenacted in the movie "Tora Tora Tora." While the TV screen pictured Japanese bomber pilots, their destructive deeds done, triumphantly returning to their battleships, my youngest son, then 10 years old, turned to me for reassurance: "We got back at them later, didn't we, Dad?"

A typical reaction of an American boy. Except that my son Phong is not a typical American boy.

Phong, his two brothers and his sister are of Vietnamese origin, the children of my wife's first marriage and hence legally my stepchildren. Phong, now just turning 15, first arrived in the United States less than seven years ago and lived there only half that time before I was again assinged abroad in the Foreign Service.

Phong was with my wife, Dzung, and me in June when we made a pilgrimage to the American military cemetery at Omaha Beach in Normandy. All of us stood speechless as we looked out across row after row of white crosses and Stars of David marking the graves of nearly 10,000 of the American soldiers who died in the area. Phong broke the silence.

"Dad," he asked, "do we have any relatives who fought in Normandy?"

"No, son. Some of us almost made it, but not quite."

"Oh," Phong said, his voice edged with disappointment.

In their newly adopted country, Phong and our three other children learned English with remarkable speed, to the point that they sometimes chide their mother for her lingering Vietnamese accent. What is even more remarkable, though, is how quickly and fully they have identified with the United States.

Soon after we moved into a home in Vienna, Va., the four of them knew all about the Washington Redskins - much more than I ever knew or cared to know - and rooted for them with the fervor of longtime Washingtonians.

After we moved to Brussels, it was Thuy,the oldest, who insisted we display it on the rear window of our station wagon. He wanted to make sure that people did not draw any erroneous conclusions from our Belgian license plates.

These four little newcomers from Asia soon adopted the uniform of American kids - jeans and sneakers - and the habit of playing rock music at full blast. They have brainwashed me into almost liking rock, at least the mellow kind.

They have not rejected everything Vietnamese. They still enjoy eating Vietnamese food - not every day, but every second or third day (as do I). After a few weeks of English language instructions with an elementary reader in Saigon, Phong and his sister, Han, briefly considered changing their names to Dick and Jane, but with no pressure from Czung or me, all four have kept their Vietnamese "first" names, coupled to the Senser family name.

But they are Americans now, and want nothing more than to return to the United States. A couple of years ago, Dzung and I took Phong and his brother Son (yes, Son is a Vietnemese name) on a short visit to Paris to see the Eiffel Tower, Notre Dame and other marvels of France. Driving back to Brussels, I asked them where, of all places of the world they had visited, they most wanted to live.

I thought that they might name Paris or Brussels or Tokyo or London or Saigon. With one voice, however, they shouted: "Northern Virginia!" and wondered how soon we would go back.

My children's evolution from Vietnamese into Americans says something about how easily the young can adapt to new environment to which they have adapted.

I remember the afternoon in early 1973 when we first drove up to our newly acquired house on a cul-de-sac in Vienna, Va. Within seconds, we were surrounded by a dozen curious neighbourhood children.Curious, but also very friendly. One of them asked our children: "Wanna play kickball?"

And even though they had never played kickball and knew very few words of English, they played kickball and managed to communicate with their new friends.

That - more so than the citizenship ceremony of several years later - was their initiation as Americans CAPTION: Illustration, no caption