Why is it that so much time and energy in government are wasted on secondary issues? It is absurd to find a Senate committee and the Reagan administration confronting each other over the President's nomination of the head of the Arms Control and Disarmament Agency. Instead of dealing with substantive arms issues, attention is being diverted to a political standoff.
The Senate Foreign Relations Committee cannot be faulted for challenging the fitness of Mr. Adelman to be in charge of so crucial a government agency. The legislators are right to refuse confirmation if and when the vote is finally taken. Indeed the President sparked not a few expressions of disbelief when he insisted that ''the young man is eminently qualified for this,'' when Mr. Adelman's own testimony before the Senate committee totally belied such a claim. Republican Senator Charles Mathias, concerned about the inappropriateness of the choice and warning of a confrontation with the White House, went so far as to say that the President ''is caught between the right wing and the right thing and has lost the initiative.''
Whether postponing a vote and putting the onus on President Reagan to withdraw the nomination was wise is open to question, however. Mr. Reagan seems determined to hold firm, something which might have been anticipated given the reluctance of any president to be seen giving in to congressional pressure.
In any case, Mr. Reagan is left with a question of fundamental importance: Does he want in ACDA someone who is perceived as serious about nuclear arms control - or as actually dubious about it? The President has gone to great lengths in recent weeks, including dispatching his vice-president to Europe, to try to persuade Europeans that he is genuinely seeking an arms accord with the Russians. He seems to have picked up credibility on this score. Yet doubts remain, fed in part by the state of disarray in ACDA.
It is all so needless. There are US arms experts of proven capacity and dedication to arms control who share the President's conservative views and who could fill the ACDA post with distinction. Brent Scowcroft, a member of the presidential commission looking into the MX, is an obvious choice. William Hyland, close associate of Henry Kissinger during the SALT I negotiations, is another possibility. There are others.
The President was right when he said in his press conference Wednesday that ''arms reduction should not be a political problem on the Hill.'' But he himself has created the problem, perhaps by following poor advice from his aides. Now he must find a way out. Whatever political discomfort it might entail, he nonetheless could regain that ''lost initiative'' by withdrawing Mr. Adelman's name and starting over. If he chooses to take the issue all the way to a Senate floor vote, he might win a political point. But how effective could Mr. Adelman then be as ACDA director, even if he had the credentials for the job?
In the long run, there can only be benefit in correcting a mistake.