If there is anything to be learned from the terrorist hijacking of the TWA airliner and the subsequent imprisonment of 40 Americans in Beirut, it is that terrorism is likely to be the preferred form of warfare against the United States and that the United States is not sufficiently equipped to handle it.

Nuclear weapons and ships are useless against terrorists. The Reagan administration's great defense buildup has produced an arsenal that is totally inappropriate to the form of war that the country is facing.

"I'm as frustrated as anyone," President Reagan told the nation during a televised news conference immediately following the hijacking. "I've pounded a few walls myself when I'm alone about this. It is frustrating . . . . You have to be able to pinpoint the enemy. You can't just start shooting without having someone in your gunsights."

Reagan ruled out a generalized retaliation because, as he put it, "I would be sending a number of Americans to death if I did it."

Might may make right; but when terrorists seize American hostages, that's about all it does.

Last September, as part of the defense authorization for 1985, Congress approved $16 million for the establishment of a U.S. Peace Institute. Supporters hoped it would become a center for research and development in conflict-resolution techniques, and for the training of American and foreign leaders in mediation.

The institute would operate independently of the State Department but be available as a third party that could provide highly skilled mediators to assist in crises such as the current one.

The idea had been advocated for years by former senator Jennings Randolph (D-W.Va.), and Sen. Spark Matsunaga, (D-Hawaii), who introduced legislation to create the institute when he arrived in Congress in 1963.

It took more than 20 years of extensive citizen lobbying by the Peace Academy Campaign before legislation establishing the institute was passed. And when it was, much of the original concept was diluted to satisfy conservatives who feared another bureaucracy -- and a left-wing one at that. Funds to build a central facility were deleted, the institute was stripped of the ability to grant degrees and a fourth of its funds were earmarked for existing graduate programs in peace studies.

A 15-member board of directors was established, no more than eight of whom can be from the same political party. The board includes four ex-officio members, including the secretaries of state and defense, and 11 people who were to be nominated by the president by April 20. The administration has yet to send any nominees to the Senate. Instead, it has circulated a list of amendments to members of Congress for changes it wants in the way the institute is run.

Rep. Dan Glickman (D-Kan.), the chief House sponsor of the institute, says the purpose of the amendments is "to give the administration much more control over the day-to-day operations of the Peace Institute."

"For the most part, they're unacceptable," he said. "I and others might work in good faith if they sent the list of nominees down. They're in real violation of the law now."

Without the board, there is no recipient for the $4 million that has been appropriated for the institute so far. The administration, which has never backed the concept of a peace institute, has by inaction kept it from coming into existence.

"One of its purposes," says Glickman, "is to train diplomats as well as people in the private sector on the causes of conflict. I can't help but believe the institute would have done a better job in training people . . . . The past few years have shown we know very little about the Lebanese government, its people, who the Shiites are. We have no more resources to deal with this problem than 20, 30 or 40 years ago.

"The ships off shore are impotent. For a while, we didn't even know who we were dealing with. [The institute] would be a reservoir of different conflict-resolution techniques, in a nonpartisan, nonideological sense, a resource base where our government and others could have gone and drawn on the skills of people. Right now, we are passively sitting by and letting Mr. Nabih Berri the Moslem leader control the agenda. We're sitting by and flexing muscle."

Trained, experienced negotiators with expertise in the Arab world, he said, could have provided a middle ground between sitting passively by and a show of military force.

A superpower would have been a bit less helpless -- and appeared less helpless -- and the president might not have been pounding the walls.