Nunn for veep?

SO far as I have been able to find out, Sen. Sam Nunn of Georgia has never told anyone whether he would accept second place on the Democratic ticket if it were to be offered to him. But from the moment it became clear that Gov. Michael Dukakis of Massachusetts, barring unforeseeable changes, is going to be the nominee of the Democratic Party for the presidency, the idea of Senator Nunn as the Dukakis running mate has been uppermost in political speculation.

One reason is obvious. From a politician's point of view Mr. Nunn makes almost a perfect balance with Governor Dukakis. One man is from the industrial Northeast. The other is from the still partly agricultural South. One is from New England. The other is from the Confederacy. One is mildly liberal, and the other is mildly conservative. The one thing missing is the great West.

There is one other less obvious respect in which the Dukakis-Nunn combination would make a lot of sense.

Mr. Dukakis has limited experience in military matters. (About all we know of him and the military is that he is allergic to the idea of sending his Massachusetts National Guard to Honduras to try to intimidate Daniel Ortega of Nicaragua). But military matters are going to be a high-priority issue during the next four years. Everyone in high positions in national affairs knows that military spending is going to have to come down.

The great problem will be to cut and trim wisely. Choices are going to have to be made. Does the United States need both a B-1 and a Stealth bomber? Can the US afford both the MX and the Midgetman missile? Does the US Navy need 15 aircraft carriers, or would 12 be sufficient?

Should new aircraft carriers and missile-launching submarines be the world's largest, or would the US do better to have smaller carriers and submarines, but more of them - fewer eggs in each basket, but more baskets? How far and how fast should the US explore the possibilities of ``star wars''?

If you could take a poll of the members of Congress asking who could best be trusted to make such difficult choices, the result almost unanimously, from both parties, would be Sam Nunn. He is recognized as beyond doubt the most knowledgeable person in either house in such matters, and probably the wisest.

Nunn is known as being strong for defense, but selective and prudent. He would be the obvious person to be head of the Defense Department - if the Democrats should win. Could he be both vice-president and secretary of defense at the same time?

No one has yet come up with any other name that would add so much strength to a Dukakis ticket. It is so obvious that Richard Nixon has mentioned it. Mayor Edward Koch of New York City waxes lyrical when he talks about Nunn as the vice-presidential candidate of his party. Jesse Jackson's lieutenants speak highly of Nunn.

Whether even Nunn of Georgia could bring states of the old Confederacy back into the Democratic Party on election day is questionable. But Nunn's presence on the ticket would be reassuring to people who worry about adequate defense. His lack of enthusiasm for everything the women's movement wants would be comforting to many Southern whites.

If the Democrats truly want to win the 1988 presidential elections, they had probably better manage to take two essential preparatory steps. One is to get Nunn on the ticket. The other is to get Nunn on the ticket with the consent and with the full support for the whole ticket of the Rev. Mr. Jackson.

A Dukakis-Nunn-Jackson team would be hard to beat. Anyone who could put that team together would have earned the title of ``master politician.''