On her first vacation in 18 months, Lamia Doumani arrived in Beirut just in time for the bombs. The 45-year-old secretary from Kensington reached the Lebanese capital to visit her mother on June 3. They spent the next day huddled in the bomb shelter of their apartment building and for the next five days slept in their clothes.

"I cannot describe how scared everyone was," she says. "We didn't dare sleep in our nightgowns. We lost electricity and water; the children cried; those weapons they used, the American weapons, scared everyone. There was bombing everywhere in Beirut; three apartment buildings not far from our place just went down with everyone inside."

Shaken but unscathed, Doumani returned to her suburban Maryland home. Now she anxiously watches the TV news and waits for a telephone call for word of her mother and for political developments in the Mediterranean country to which an estimated 2 million people in this country trace their roots.

Like Doumani, many of these Lebanese Americans are outraged by the killing of civilians in Beirut and angry at what one of them calls "the long, deep silence" of the U.S. government on the Israeli invasion. "As an American how can I live with my conscience knowing that my tax dollars are going for cluster bombs to Israel?" asked Doumani's brother, George, a geologist who came here 30 years ago and is now a naturalized citizen.

The 5,000 or so residents of the Washington area who trace their origins to Lebanon have responded to the current crisis in the Mideast with an outspokenness and activism unusual for an ethnic group that has traditionally shunned politics.

Since they began coming to this country in large numbers at the turn of the century, Lebanese--who make up about two-thirds of the Arab Americans in the United States--have gained a reputation for financial success and rapid assimilation into mainstream American life. Partly because of a sense that they are Americans first, they have had little appetite for involvement in the internal religious and political feuding that has racked their homeland and have shown little interest in political activity or lobbying on behalf of Lebanon.

But events in Lebanon over the past seven years, starting with the 1975 civil war and followed by foreign occupations--first by Syria and now by Israel--have had an impact. "People have begun asking,'Who am I?' They have begun searching for their roots," says Safa Rifka, a physician who came to Washington in 1975.

They also have begun to protest what they feel is the pejorative image of Arabs in the United States. "It's really hard for people to understand the intensity of anti-Arab propaganda in this country," says James Zogby of the American-Arab Anti-Discrimination Committee (ADC). "Arabs are called 'rag head,' 'camel jockey.' We are still victimized by the mass media--look at Abscam,"

For Marcell Anthony, 33, a lawyer, the invasion of Lebanon has been a capstone in her growing ethnic awareness. For the first time she has marched, lobbied on the Hill, and stood at Metro stops passing out leaflets. "I know the invasion has committed me to striving to bridge that gap between Lebanon and the whole Middle East and the United States which I feel exists because the word 'Arab' has been repeatedly utilized to mean 'terrorist,' 'ugliness,' or 'a person who is nothing,' " she says.

"I've been made aware of this discrimination over the last 10 years, more intensely over the past three years, and because of the invasion I have decided that for the rest of my life I am going to consciously be an advocate for the Arab point of view in the best way I can."

Sara Najjar, a 39-year-old government lawyer, was born in Lebanon and came to this country as a child. She recalls that in grade school she tried to discard her heritage in order to be accepted by her classmates. "We Lebanese loved America so much and we assimilated so well we forgot about our past," she says. "There was a tendency to discard our culture and heritage, to ignore or block it out.

"The change for us really began with the 1967 war when Israel attacked the Arab countries. Something happened which we felt we should know more about. This sentiment has been building ever since and this war was just the last straw."

"What happened in Lebanon was a rude awakening for many Lebanese Americans," she adds. "It has caused us to experience firsthand the double standard which exists in the media and in our government's policies toward Israel and the Arab countries. It has shocked many Lebanese Americans into realizing the discrimination which exists in this country against people of our heritage."

Examining their roots, in many cases for the first time, Lebanese Americans have adopted differing attitudes toward their ethnic background, with some taking a purely Lebanese outlook and others a pan-Arab stance.

Organizations such as the ADC, formed in 1976, and the 10-year-old National Association of Arab Americans, see Lebanon's future and the Palestinian problem as issues to be solved in tandem and in the context of the wider Arab-Israeli conflict. The need to find a homeland for the Palestinians is the core of the Mideast conundrum,they say.

"The only way for a permanent solution to the tragedy of Lebanon is . . . to get Israel to agree to the creation of a Palestinian state. The root cause of the problem is Israel," says NAAA president Richard Joseph.

"The majority of Arab Americans don't support any rigid ideological position; they don't want to be involved in inter-Arab struggles," says Zogby. "But in a general way, the majority of them feel the Palestinians should have a state, that Lebanon should be at peace with its territory intact and that it should be a democracy."

Both groups include Muslims and Christian Arabs but their memberships are predominantly Lebanese Americans of Christian heritage, reflecting the makeup of Arab Americans in this country.

They see their role as a counterpoint to the powerful Israeli lobby and have roundly denounced the Israeli invasion as an attempt to impose a pro-Israeli government in Lebanon and wipe out the Palestine Liberation Organization militarily and politically. To them, the PLO is not a terrorist group, but as George Doumani puts it, "the expression of Palestinian nationalism."

Opinion on the PLO, however, is far from unanimous. Others regard it as a terrorist organization--a view held by many members of the American Lebanese League, a more conservative group founded in 1976 to focus specifically on the problems of Lebanon, according to spokesman Robert Basil.

For members of this group, Lebanon comes first, Basil says, and "It's not right to hold the Lebanese people hostage until there is a settlement. We feel the Lebanese problem should be stopped and corrected now, without waiting for 5 to 10 years for the world to solve the Palestinian problem."

Unlike the two other groups,the league has made no denunciation of Israel's invasion of Lebanon and in a full-page ad in The Washington Post welcomed it as an "unprecedented opportunity" to "save Lebanon."

This position has led to charges by both Lebanese and non-Lebanese observers that the league works closely with the Jewish lobby here. Basil says the Israelis have simply adopted a stand the league has had for six years. He calls the rival groups "extensions of the Arab League."

None of these groups commands the activism, interest, loyalty or financial backing comparable to Jewish-American organizations. And their influence with U.S. decision makers, compared with pro-Israel lobbies, is likewise limited.

Lebanese-American community leaders say they count their blessings in small ways. They point to criticism of Israel's actions by a handful of members of Congress and they mention the volunteers, more than in past crises, who have come out to demonstrate against the invasion, to pass out leaflets at Metro stops and to help lobby on Capitol Hill.

These Lebanese Americans also sense more sympathy for their positions among Americans in general. "More people are marching, young people who never turned to us in the past are calling; the Israelis have gone too far this time," says Helen Haje, who has been active in the Arab American community for more than 25 years.

It is difficult to gauge which orientation has more support among Lebanese nationwide, but to judge by turnout at events here, the dominant support in the Washington area is for the viewpoints of NAAA and ADC.

"You cannot blame the Lebanese for feeling that the Palestinians have caused all the problems in their country," says George Doumani. "But it was the Israelis who first created the problem by kicking them out of Palestine. They went first to Jordan, and now they are being kicked out of Lebanon. This shows that military action to solve the Palestinian problem is not a solution. Find them a home, that's the solution."