WITH the Reagan administration's second term almost at midpoint, a lot of high officials must be beginning to ponder what they will do next, and what government record they will leave for history. Over lunch with a few columnists in his Pentagon dining room this week, Defense Secretary Caspar W. Weinberger was persuaded to reflect a little on his tenure.
Mr. Weinberger has been about as battered a Cabinet secretary as any in President Reagan's team.
He has taken it on the chin for promoting substantial increases in defense spending during times of economic difficulty. He has had to take the heat for instances of Pentagon misspending and overspending (although he points out that the Pentagon itself uncovered a lot of these). He has been criticized for alleged foot-dragging on such operations as the downing of an Egyptian airliner carrying the Achille Lauro hijackers, and the air strikes against Libya. By contrast, he has been criticized for being too hard line and unyielding on American negotiations with the Soviet Union.
Has it all been a much harder job than he expected? He gives a wry little smile. He expected it to be a tough job, he says. And he hasn't been disappointed in those expectations.
Nor have the Soviets -- his principal concern as defense boss -- disappointed him in living up to his expectations of them.
About Moscow, he remains cautious, suspicious. In the new Soviet leader, Mikhail Gorbachev, he sees a different style, but not much change in content. Mr. Gorbachev is ``probably not in full control''; the Soviets have a collegial system of government and Gorbachev has to please a lot of people. ``He cannot be at odds with his military.''
Weinberger is not sure the Soviets are serious about a summit meeting this year.
On Nicholas Daniloff, the American newsman arrested by the Soviets, ``We want to get him out.'' But, in a reference to suggestions that the United States trade a Russian arrested on espionage charges for Mr. Daniloff, Weinberger believes ``selective law enforcement is not a very good idea.''
He thinks Soviet talk of deep arms reductions is progress, but he doesn't believe that is because of any change of heart in Moscow. He thinks that is a response to regained American military strength.
In Afghanistan he sees no Soviet concession. Although the Soviets announced recently a modest pullout, Weinberger says those were motorized units not engaged in combat, and there is no reduction in troop levels overall. He is concerned about the expanded Soviet military presence in the Pacific and the Far East. He looks with a jaundiced eye on Soviet air and naval activity out of Cam Ranh Bay, the base built by the United States in Vietnam. He thinks the Soviets are cozying up to North Korea.
Thus he has no regrets about his sometimes unpopular push for more defense spending. ``We had to do something quickly, effectively. We had to regain our ability to deter, and to a great extent we have accomplished that. We had to make large, but necessary, expenditures on defense.''
It is sad, he reflects, that efforts to deter war are misinterpreted as the desire to make war.
But his thesis is that you ``cannot relax for a minute.'' The United States cannot give up areas of the world. It must be ready to deal with Soviet aggression wherever it turns up. ``If you don't deal with it, they get a foothold.''
If the United States is ready to use its military strength, says Secretary Weinberger, that makes it less likely that it will actually be called upon to do so.
He thinks the morale of the American military is higher now than it was when President Reagan assumed office. He thinks there is more pride in the current equipment.
But he says reflectively that the ``job is never finished.''