Ten years ago, Charles E. Goodell was a Republican senator from New York ardently campaigning to end the Vietnam war.

Today he is a lobbyist, chairman of a company called DGA International which specializes in representing foreign governments and companies.

One client is the government of Mococco, which recently paid DGA $882,550. DGA's mission: to help portray Morocco as a "stable influence in the unsettled political environment of Africa," and to win U.S. government approval of a proposal to sell Morocco U.S. arms so it can put down a rebellion in the western Sahara.

DGA Iinternational has had other notable foreign clients in the past few years. It collected $3.6 million from 1975 to 1980 from Aerospatiale of France to help win landing rights for the Concorde here. It got $600,000 from the German group Krauss-Maffei, which was hoping to sell the Pentagon its Leopard II tank. It got $200,000 from Thompson CSF of Paris for a campaign to sell the Pentagon on Thomson's Atlis II attack system, and it got $1.7 million from Airbus of France for a campaign to help sell the A300 passenger jet to U.S. airlines.

Foreign agentry -- acting as the agent to foreign government or business before Congress or an executive agency or in efforts to influence U.S. public opinion and policy -- is one of the thriving industries in the nation's capital. DGA is only one prominent example.

Under the Foreign Agents Registration Act, those who represent foreign clients must in most cases register and file financial reports with the Justice Department.

The roster there glitters with widely known names. It reads like a reunion of former members of Congress and high officials of the executive branch:

The law firms of Clark Clifford, the former secretary of defense, and his partner, Paul Warnke, who helped negotiate the strategic arms control accords; of former secretary of state William P. Rogers; of former under-secretary William D. Rogers; of ex-senator Marlow Cook; of former Senate Foreign Relations Committee chairman J. W. Fulbright; of ex-senator Joseph D. Tydings; of former House Ways and Means Committee chairman Wilbur Mills; of former secretary of interior Stewart L. Udall, and ex-CIA director William Colby.

Although foreign nations maintain embassies, chanceries, trade and military missions here, these countries and their companies plainly feel a need for help when approaching the U.S. government on matters ranging from commercial arrangements, tariffs, licensing of planes and uses of scientific processes to immigration cases involving their nationals.

In part, the foreigners are buying legal expertise. But they also are buying political clout and access to key government leaders.

These contacts, ease of approach and a feel for the U.S. Congress and the government establishment can't be achieved by any foreign nation directly through its own personnel, even a nation as sophisticated as France or Britain. You have to hire an American who knows Americans, knows every nuance of the scene and works it instincitively.

That's why foreign principles pay very big money to U.S. lawyers, lobbyists and public relations specialists.

"There's a gulf of communications, a lack of understanding of the nuances of our system" that needs to be bridged in the public interest and that only an American can bridge," said Goodell in a phone interview.

A review of some, though far from all, of the registrations under the Foreign Agents Registration Act shows that clients often go for the big names, persons of proven contacts and reputations. c

Take DGA and the Concorde. The firm was founded in 1969 by Donald G. Agger, whose initials it took for its name. Agger had just finished a two-year stint as assistant secretary of transportation and earlier in his career had served as U.S. delegate to the NATO infrastructure committee.

Agger brought with him several former government associates. In an early letter to one client, he pointed out that two such associates had worked on mass transit in government and "have established personal and professional relationships within the field that are of great value."

When DGA bagged the Concorde contract, it faced a massive problem of persuasion at many levels of government. Government agencies had to be persuaded the Concorde could meet noise and environmental standards. There was a certain amount of public hostility to overcome. Local government agencies in New York, as well as the federal government, had to be dealt with.

Finally, Congress might act to block the Concorde. Neither Aerospatiale, Air France nor the French government really had the expertise to handle these matters. They turned to Agger.

The successful Concorde campaign involved thousands of hours of preparation of environmental and noise reports, appearances at public proceedings, contacts with Congress and executive agencies, and followup work to see that approval once given wasn't canceled.

Goodell, for example, who registered with the Justice Department as a DGA director in connection with the Concorde and the Leopard tank cases early in 1976, reported in 1977 that he had met on the Concorde matter with Alan Sagner, chairman of the Port of New York Authority, which runs John F. Kennedy International Airport, one potential landing site; with Transportation Secretary Brock Adams; with Linda Kamm, Department of Transportation general counsel, and with Philip Trimble of the State Department.Goodell's law firm, Hydeman, Mason and Goodell, did much of the legal work on the Concorde, at one point averaging more than $25,000 a month in law fees from DGA for the work. They had 11 lawsuits pending at one time.

Later, Goodell reported that on behalf of Morocco, he spoke in 1978 and 1979 with James Bishop of the State Department, with a CIA official, with Undersecretary of State David Newsom and with a whole flock of members of Congress, among them Senate Foreign Relations Committee Chairman Frank Church (D-Idaho), senior committee Republican Jacob K. Javits (R-N.Y.) and House Foreign Affairs Chairman Clement J. Zablocki (D-Wis.).

As anotehr example, in 1969 the Australian Meat Board wrote to Warnke of its convern for free access for Australian meat to the U.S. market. It offered a $50,000 retainer for Clifford and Warnke's services.

According to government records, the Australia Meat and Livestock Corp., a successor group, paid Clifford and Warnke $200,000 in retainers from Sept. 30, 1977, to Sept. 30, 1979. Among the activities undertaken by members of the firm for this group in 1978-79: phone calls to the House Ways and Means international trade subcommittee, filing of comments with the House Agriculture Committee on meat import problems, contact with the Senate Finance Committees, phone calls to the White House. Members of the firm seem to have eaten well too. Among its expenses was a dinner costing $1,003.89.

The firm also sent a letter to Algerian Ministr of Industry and Energy Belaid Abdessalam Feb. 11, 1971, agreeing to represent Algeria for $150,000 a year plus expenses. Activities later included discussions with the State Department on applications for imports of gas from Algeria, advice on "administrative and legislative developments in the U.S." and legal advice. The arrangement ended in 1978, according to the records.

Colby, the former head of the CIA, registered in 1978 for the Political Public Relations Center of Japan, pledging to undertake "consultation, study, reseach and presentation of opinions and suggestions for foreign prinicipal and its clients in Japan." From late 1978 to Nov. 30, 1979, he or his partners were listed as receiving about $33,000 in fees and expenses.

In 1977 the the law firm of Duncan, Brown, Weinberg and Palmer registered for Foothills Pipelines of Canada, agreeing to provide "legal services and lobbying with the executive and legislative branches of both the Canadian and the U.S. government" to promote to plan by Foothills (and a U.S. associate) for a huge natural gas pipeline from Prudhoe Bay to the United States, Weinberg was solicitor of the Interior Department under former (1961-69) secretary of interior Stewart L. Udall, who, a few days afterward, filed a registration himself, saying he would be "of counsel" with Duncan, Brown.

A letter to Udall from one Foothills spokesman contained $30,000 in advance for his work at $200 an hour. Later in 1977, Duncan, Brown indicated it had received $82,877 in receipts from Foothills.

Among those it listed as having contracted on behalf of Foothills were Sens. Mike Gravel (D-Alaska), Ted Stevens (R-Alaska), Gary Hart (D-Colo.), Dennis DeConcini (D-Nev.) and Dale Bumpers (D-Ark.), most of them members of the Senate Energy or Environment committees; House Interior Committee Chairman Morris K. Udall (D-Ariz.), Stewart Udall's brother; and Assistant Interior Secretary Guy Martin.

The Foothills plan subsequently was approved by Canada and President Carter.Udall, who still represents Foothills, said in an interview that "it was not me" who contacted Morris Udall. "I've never lobbied my brother."

Ex-representative Wilbur Mills (D-Ark.), once all-powerful chairman of House Ways and Means, became associated with the law firm Shea Gould Climenko and Casey after leaving Congress. He indicated in a registration that he would represent the New Zealand Wool Board, which paid the firm a $15,000 retainer, possibly with the aim of seeking reduction of duties.

The list goes on and on. The law firm of former senator and former representatives David Henderson (D-N.C.), Graham Purcell (D-Tex.) and Orvil Hansen (R-Idaho) registered last fall for B.A.T. Idustries of London, a giant umbrella firm that owns British-American Tobacco. Interest: taxes here on foreign affiliates of firms doing business in the United States.

William P. Rogers, the former secreatry of state, heads the firm Rogers and Wells, which has long had many international clients. In 1975 it registered for Air France to help work on the Concorde matter, reporting nearly $500,000 in receipts from August 1975 to August 1976.

One of those working directly on this account was former assistant secretary of the treasury Eugene Rossides. Rossides wrote Sen. Bob Dole (R-Kan.) opposing an amendment to block the Concorde, and spoke to top Senate staffers Brian Atwood (now an assistant secretary of state) and Sally Shelton (now ambassador to Barbados).

All this is perfectly legal, but Common Cause's Fred Wertheimer believes that pouring so much money into campaigns to influence the legislative and executive branches distorts the political process, whether it's done by lobbyists for domestic principals or foreign governments and companies.

"There is a basic problem with the amount of resources being brought to bear on the political process," said Wertheimer. "The stakes are so high in many government decisions that both foreign and domestic interests are willing to spend large amounts of money. I'm not sure whether spending by foreign interests is any worse than by domestic."

DGA Vice President Lloyd Preslar says he doesn't think his firm's activities distort the political process.

"One can say we're a gun for hire, but I don't think that's true."

He said the firm thinks long and hard about what its goals are before it takes on any client such as Morocco. "We didn't casually take on Morocco. It took a good while to satisfy ourselves where we thought American interests were."

Preslar also said the amounts of money being paid by Morocco and other clients look very big in gross figures but are much smaller after the deduction of travel, legal research and services, transcripts, and the time involved in meetings to work out positions and commit them to paper.

In the case of the Concorde, the firm incurred tremendous costs for noise and environmental research, legal costs and the like, he said.

Goodell, in a phone interview from Florida, said he doesn't make much on his actual lobbying activities for DGA. For Morocco, he gets $110 an hour when he lobbies and nothing else from DGA. He doesn't get anything as a director. The financial benefit to him from his association with DGA comes through payments to his law firm for legal services, as in the Concorde case.

As for the Moroccan cause, he said he thinks its's a good one, far different from the Vietman war in its final stages. Morocco, he said, "is the best of the Islamic nations in terms of our idealistic principles. This is a war that may have some indigenous involvement [on the part of the rebels] but that," said Goodell, "is overwhelmed by the Algerian-Libyan involvement and they're not doing it out of idealistic principles."