What was going on when I was born?

Congress finished its business and left town for the year tonight. Before leaving, the lawmakers gave final approval to legislation that raises the national debt ceiling, provides $250 billion for the Defense Department, increases the American contribution to the International Monetary Fund by $8.4 billion and authorizes the expenditure of $15.6 billion for subsidized housing programs. President Reagan fought hard for most of those bills and is considered certain to sign them. He does not like the housing legislation, but sponsors maneuvered it into the same package as the monetary fund increase, leaving the President little choice but to swallow the whole thing.

The United States said today that the Soviet Union had made a new, informal offer to cut by half the number of SS-20 missiles aimed at Western Europe if NATO dropped its plans to deploy 572 new American missiles in Europe. The proposal was turned down by the Reagan Administration. In Moscow, the Soviet Defense Minister, Dmitri F. Ustinov, issued a statement accusing the United States of having deliberately doomed disarmament negotiations. (Page 6.) But a West German Government spokesman, reacting earlier to the informal Soviet offer in Geneva, welcomed what he termed Soviet signs of flexibility in the arms talks.

The fervid band of people who served John Fitzgerald Kennedy is scattered and diverse now. Some have grown old, others conservative or conventional in the 20 years since the Kennedy Presidency was ended by an assassin's bullet in Dallas. But they are in agreement that his legacy is indelible, whether it is no more than a myth embedded in the national conscience or is based on tangible accomplishments such as space exploration or the Peace Corps. ''Like Franklin D. Roosevelt, he inspired an idealism about the kind of government we should have, and he wanted to harness that,'' said Arthur M. Schlesinger Jr., the historian and Kennedy aide who has been trying to hold back a tide of negative revisionism about the Kennedy era. Harnessing idealism, Mr. Schlesinger said in a telephone interview, ''is what America is all about.''

The Reagan Administration, responding in advance to a television dramatization of a nuclear war and its aftermath, is stepping up its efforts to persuade the public that its policies are the best way to prevent such a war. The ABC-TV film, ''The Day After,'' to be broadcast Sunday, has become a rallying point for opponents of the Administration's nuclear arms policies. White House officials have recently made clear their concern that its showing would put the Administration on the defensive. The film graphically depicts the destruction of the area around Kansas City, Mo., in a nuclear attack. Publicity about the film has already thrust it into the larger political debate about nuclear arms.

The Reagan Administration is considering sanctions against Salvadoran exiles in the United States who are strongly suspected of paying for and at least partly directing death-squad activities in El Salvador, according to a senior Administration official. The actions being considered include ordering immigration officials to reconsider the visas of the suspected exiles and investigating their financial dealings in the United States, the official said. To avoid extended deportation proceedings, he said, the suspects may also be refused entry back into the United States the next time any of them travel abroad. 'We've Had It' ''We've had it with these guys,'' another United States official familiar with the issue said. ''If they don't clean up this time, we're going to do something.

Argentina announced today that it had developed the technology to make enriched uranium, giving it the capacity to make the fuel for nuclear explosives. Rear Adm. Carlos Castro Madero, president of the National Atomic Energy Commission, said at a news conference that Argentina would use its new nuclear capacity only for ''peaceful ends.'' But he said Argentina would not submit to the inspections called for in international treaties against the spread of nuclear weapons. Argentina has not signed such agreements, and the admiral charged that they discriminated against developing countries.

Governor Cuomo and Mayor Koch announced agreement yesterday on a project that would involve more than $1 billion in commercial, industrial and residential development in sections of the New York and New Jersey waterfronts. The agreement followed nearly eight months of sometimes bitter discussions between state and city officials. Approval by the New York State Senate is now the only remaining obstacle to the project, which has already received New Jersey's support. Under the plan devised by the Port Authority of New York and New Jersey, the agency would spend up to $125 million to prepare a 70-acre tract in Hunters Point, Queens, for private development - the largest such project ever contemplated in the borough.

After hours of heavy shelling and ground fighting, Yasir Arafat said tonight that his forces had regained a ''large area'' of the Beddawi refugee camp on the edge of the city. But Palestinian rebels who fought their way into the camp two days ago and held most of it Thursday said through a spokesman in Damascus today that they had repulsed three attempts by Arafat forces to advance and had lost no ground. The heaviest shelling of the 15-day battle made it impossible for reporters to get close to the battered camp to verify the conflicting statements. Heavy Shelling in Tripoli There was heavy shelling in some parts of Tripoli, too, and ambulances raced through empty streets, sirens wailing. One of those seriously wounded was a 19-year-old Lebanese soundman for a British television service. He was hit by shrapnel when a rocket exploded near the elementary school that has been turned into a press office for Mr. Arafat.

A military judge today condemned 4 leftist militants to death and sentenced 111 others to varying jail terms, an official announcement said. The announcement said 68 others were acquitted in the trial of 183 purported members of Dev Yol, a guerrilla group active in big cities before the military takeover in 1980.

This city is invaded each day by an army of 3,000 Sri Lankans. Armed with brooms and mechanized street sweepers, they advance quietly and efficiently through the city's markets and grand boulevards. Their mission is to keep Riyadh clean. The results are staggering, Saudis and foreigners agree. Ten years ago Riyadh was one of the dirtiest, dustiest cities in the Middle East. Today the city is relatively spotless. Nevertheless, Rodney R. Proto, managing director of Browning-Ferris Saudi Arabia Ltd., a joint Saudi- American venture that has a five- year, $233 million contract to clean the city, is not satisfied. The company recently began a major campaign, aimed at children, to raise public consciousness about the importance of cleanliness.

Syria is rapidly eclipsing Egypt as the predominant Arab military power in the Middle East, according to Israeli and United States military analysts. The officials attribute this to Syria's mobilization of manpower and to continued increases in the number and quality of Soviet weapons reaching Syrian forces. The Israeli and United States sources who take this view also say the presence of 5,000 to 7,000 Soviet soldiers in the country has strengthened Syria's defensive position. Syria's present tactical deployments, intelligence officials said, make it virtually certain that any deep penetration of Syrian airspace by Israeli fighters and bombers would meet heavy antiaircraft fire, both from missiles and guns, that are largely manned by Soviet personnel. Only one of the four major surface-to-air missile bases in Syria is now said to be operated by Syrians.

Western and some third-world diplomats here predict that Iraq will eventually use its new French-built warplanes in the war against Iran, but will probably not use them against the huge Iranian oil terminal at Kharg Island. The Teheran Government has repeatedly said an attack on Kharg Island, in the Persian Gulf, would lead to an Iranian blockade of the Strait of Hormuz, through which one-sixth of the West's oil supplies pass. Although military experts have expressed doubts about the feasibility of a blockade, the Iranian threat has caused concern in Washington, Europe and Japan. In a series of interviews this week, diplomats suggested that for the time being the Iraqis intended to use their five Super Etendard fighter-bombers, delivered early last month, as weapons of psychological warfare. The Super Etendards are equipped with radar- evading Exocet missiles like those used to devastating effect against British ships in the war in the Falkland Islands last year.