Walter Mondale wasted no time turning the first question (on Central America) into the one he wanted -- "The whole question of what presidential leadership is all about." With Gary Hart it was "Where's the beef?" With the president, at Kansas City, it was going to be, from the beginning: "Where's the chief?"

And to the extent (itself debatable) that this is something voters worry much about, it was Ronald Reagan who gave the answer Mondale wanted: out for lunch.

Not altogether or all the time, but enough so to suggest that Mondale is on to something when he tests the president's grasp of what's going on, or went on, in Central America, Lebanon, nuclear arms control, Iran, or even such agencies as the Pentagon and the CIA under his command.

Advance expectations and general appearances couning for what they do, the analysts may well be right in thinking that Reagan "won" by not losing. But if you believe that command and competency do matter in the presidential conduct of foreign policy, then one conclusion seems inescapable: Reagan was overbriefed for the wrong debate.

In Louisville, he was "brutalized" by his handlers, according to Sen. Paul Laxalt, and got tangled up in details on domestic issues long before losing the thread of his closing statement. At Kansas City, the idea was apparently to keep it simple. But the president still got tangled up in details. Long before he invited us to peer with him 100 years into the future while driving down the California coast, he had demonstrated that he does not know as much as a president nearing the end of his first term ought to know about the substance of things.

Item:Submarine-launched nuclear missiles. Mondale muffed his now familiar charge when he said the presdent "doesn't know that submarine missiles are recallable" (he meant that they are not recallable). But the president's vigorous denial that he ever said such a thing requires an extraordinarily generous reading of two statements, one in 1982 and the second in February of this year. They are at best ambiguous. The president has had ample time to straighten out the record.

Item:The "terrorist" handbook for CIA-supported Nicaraguan counterrevolutionaries. "We have a gentleman down in Nicaragua who was on contract to the CIA advising, supposedly on military tactics, the contras," the president said. The manual, he added, was "turned over to the agency head of the CIA in Nicaragua" to be edited and then sent to CIA headquarters in Washington for further editing. Only a follow-up question rescued the president; it turned out he had misspoken about the CIA's having anybody in charge in Nicaragua -- "It was a man down there in that area."

Whatever the case, Reagan became the first administration official to violate what has been standard procedure for the executive branch never to acknowledge officially that the CIA is even supporting the contras (though the fact is self-evident in congressional debate over the funds for the program). Reagan's explanation runs contrary to what had been the official line: that nobody of any consequence at CIA had been involved with the manual. It also contradicts another official line: that U.S. government support for the contras is designed only to interdict supply routes from Nicaragua to the rebels in El Salvador.

Item: The U.S. Marines in Lebanon. The president left largely unchallenged two serious Mondale charges: that the Joint Chiefs of Staff had urged the president not to put the U.S. Marines in the compound that was later blown up by a terrorist truck bomb; and that the president actually ignored a Joint Chiefs' plea five days before the bombing that the Marines be removed. Reagan's only answer was that the initial decision to house the Marines in the compound was "made by the commanders on the spot."

Item: "Star Wars." The president said he had initiated a program to create a foolproof defense against nuclear weapons (not necessarily in space) with the approval of the Joint Chiefs. But the feature he dwelt on was the idea of turning over U.S. technology to the Soviets (assuming the United States makes the first decisive breakthrough), saying, "Look, here's what we can do. We'll even give it to you . . . and free mankind" from the nuclear threat forever. When Mondale took sharp issue with handing over such "advanced" and "dangerous" technology to the Soviets, the president allowed as how he hadn't really "roundtabled" the idea with the chiefs of staff, but that is just seemed to him a logical step toward his "ultimate dream" of eliminating all nuclear weapons.

Now these work habits and misperceptions strike me as sufficient to make Mondale's larger point having to do in a general way with who's in charge. But they do not tell us much that we did not already know. And that is why the real problem for Mondale, if the polls have it right, is whether enough voters think the fine points of Reagan's management of foreign policy are even worth taking into account.