The newcomers

They have been coming by the hundreds of thousands during the past decade - from nations as diverse as South Korea, Vietnam, Mexico, Jamaica, Cuba, China, Japan. They live in ethnic enclaves - often in suburban areas rather than inner cities. Their surnames sometimes have only one vowel, or include an X or Y. They are the new immigrants. And their presence is changing the face and culture of the United States.

The US, for all its efforts over the years to control and restrict immigration, is a nation that has traditionally opened its arms to the foreign-born. It is no accident that the popular inscription on the base of the Statue of Liberty begins, ''Give me your tired, your poor, Your huddled masses yearning to breathe free . . . .'' Indeed, the US has been built on the labor and enterprise of its newcomers, from the time of Colonial Jamestown in 1607 and the Pilgrims in Massachusetts in 1620 to the current Vietnamese neighborhoods in northern Virginia and the Middle Eastern communities in the Greater Detroit area.

Americans recognize their ethnic diversity - and links to the ''old country.'' Yet, ironically, most Americans are only dimly aware of the new pluralism in the United States. Too often that lack of awareness has led to misguided efforts to discriminate against legal immigrants. It has sometimes led to violence based on confusion. A young Chinese-American, for example, was killed in Detroit a year ago by two men who were apparently angered about the impact of Japanese imports on Detroit auto sales - and who mistook the youth for a Japanese. Early this year three Vietnam veterans burned a Tibetan Buddhist temple in western Massachusetts because they thought it was a Vietnamese temple.

Americans - particularly young people - would seem to need to know far more than they do about the newcomers in their midst. Legal immigration, and illegal immigration - which needs to be brought under control - should be seen as two distinct situations. Local communities have an obligation to ensure that newcomers are not discriminated against. And there is another side to the equation. Immigrants (and communities with immigrants) need to do a better job of assimilation. Many immigrants unfortunately resist assimilation.

The decade of the 1970s marked a profound change in immigration patterns. Statistics differ, depending on who is doing the measuring. But this much we know: Whereas 2 million or so foreign-born had come to live in the US during the 1950s, and 3.1 million more came in the 1960s, the number of newcomers accelerated in the '70s. Some 5.5 million foreign-born are believed to have settled here in that decade. And those 5.5 million are persons who are ''officially'' identified. Hundreds of thousands of persons entered the country illegally.

Back in 1970, 5.2 million of the total 9.7 million foreign-born stock in the US were of European origin. In 1980, the Euro ean component of the total 14 million foreign-born stock fell to 4.7 million. In 1970, 1 million of the foreign-born were of Italian origin. German-born were next - some 833,000. Foreign-born stocks from Asian nations were small by comparison.

Now jump to 1980. Analysis that year found that 2.5 million foreign-born were of Asian origin. Some 4.6 million others were from North and Central America (meaning mainly Mexico and Central American nations). And 1.3 million were from the West Indies.

Here are two other ways of looking at the change: Since 1977, 4 out of 5 immigrants have come from Latin America and Asia. During the '70s the number of immigrants from six nations - China, the Philippines, Japan, India, South Korea, and Vietnam - doubled.

Has their presence made a genuine contribution to the US? Without question. Consider just the issue of natural increase in population. The natural increase (births over deaths) is currently about 0.7 percent annually for the US. Add in immigrants (legal and illegal) and the figure is around 1.2 percent. In other words, the children of immigrants represent much of the population increase that will be needed to fill service and industrial jobs during the next several decades as the population gradually becomes older, as is now starting to occur.

Looking at the various immigration figures underscores once again how truly remarkable the American experience has been. The US is truly a ''global nation.'' Each newcomer, like the millions of newcomers before them, adds a fresh element of vitality and strength - another hue in the rich tapestry that is the United States.