Imagine a sniper gunning down 270 people on any American street and disappearing into the night. It isn't a crime the country would forget. Yet make the sniper a terrorist, the weapon a bomb and the setting Pan Am Flight 103, and you have a formula for a forgettable crime.

From the moment of the explosion on Dec. 21, 1988, the State Department, and then the Justice Department, have made communication with victims' families a low priority. It took the government days to figure out who had been on the plane that went down over Lockerbie, Scotland, so family members could be notified. The ensuing investigation has been so shrouded in secrecy that the families rightly fear little is happening.

We reported in January that President Bush had made a private pact with British Prime Minister Margaret Thatcher to downplay the Pan Am investigation. Both had learned that Iran may have paid Palestinian terrorists to do the job. Bush and Thatcher agreed that they were powerless to strike back against Iran, so the information would be best kept under wraps.

Last month, top investigators from around the world, representing all the nations with an interest in the Pan Am investigation, gathered outside Washington to compare notes. Justice Department officials first told us that there was no such meeting. Then they said there was a meeting, but ''nothing spectacular was discussed.''

The President's Commission on Aviation Security and Terrorism issued its assessment in May -- a strong treatise on America's inability to combat terrorism. The commission has no power to implement its recommendations, and the White House is still thinking about them.

Earlier this month in Sweden, 11 Palestinians with ties to the terrorist organization that in all likelihood planned the bombing, were released from jail and kicked out of the country. Swedish authorities said they had gathered all the information they could from the 11, and there wasn't enough evidence to convict any of them. They will disappear into Damascus, Syria, out of the reach of the short arm of U.S. law. Swedish prosecutors say they would have held on to the Palestinians if American or Scottish authorities wanted them to. But neither group asked.

Among the 11 were Jehad Shaaban and Samar Ourfali, both known by West German intelligence to have lived in the apartment in Neuss, West Germany, where authorities, two months before the bombing, found the makings of a bomb like the one that blew up Pan Am 103.

The apartment turned out to be a European hideout for the Popular Front for the Liberation of Palestine -- General Command, headed by terrorist Ahmed Jibril, the prime suspect in the Pan Am case.

In Sweden, the prosecutors are having problems of their own. Sweden is involved in the case because of related terrorist attacks, perhaps by Jibril's errand boys. One of the two top investigators working on the case in Sweden, Ulf Forsberg, resigned from the investigation because his superiors did not allow him to attend the meeting last month in Washington -- the international confab.

Forsberg's superiors told our reporter Paul Zimmerman that they didn't have the resources to send Forsberg to Washington. But Forsberg told us, ''That's ridiculous. Of course they could have sent me. The man who knows the case should have gone to Washington.''

Earlier this month, several family members met privately with Transportation Secretary Samuel Skinner. The families wanted to know if the government had started to implement any of the recommendations from the presidential commission. Skinner was reportedly vague, but assured them that there had been plenty of meetings on the subject.

In other meetings with Justice Department and FBI officials, family members wanted to know why the United States didn't stop Sweden from deporting the 11 Palestinians. According to family members, the response was that Attorney General Richard Thornburgh had assessed the situation on a recent trip to Sweden and decided the 11 weren't crucial to the U.S. investigation.

1990, United Feature Syndicate Inc.