Everybody has his favorite issue that is getting lost in the campaign shuffle, and mine is the need to look beyond military challenges and military responses in approaching the requirements of American policy in the Third World.

It's a question of perspective. The military component is central, most conspicuously in the Persian Gulf, where Soviet power and local instability cast a double shadow over Western access to oil. But it's far from everything. If no threat of military confrontation hung over any of its Third World interests, the United States would still face formidable challenges that could be met only by cooperation, especially in the economic field.

It's curious. To the major domestic issues being discussed in the campaign -- inflation, unemployment, slow growth, lagging productivity -- military measures in the Third World are simply no part of the solution. But though economic measures involving the Third World are part of the solution of all these domestic issues -- not to speak of a host of foreign issues (population growth, food supply and so on) -- they are off the politicians' screens.

How can one speak of "reindustrializing" America, for instance, without considering that developing countries are already among our strongest competitors even in such sophisticated industries as steel and shipbuilding? How to speak of jobs without noting that U.S. exports to developing countries have been growing a third faster than exports to industrialized countries? How to control inflation without factoring in the anti-inflationary impact of imports from developing countries? How to pursue monetary stability without considering the $400-billion-and-rising debt (much of it owed to American banks) of the oil-importing developing countries?

But you get the idea. In the campaign the candidates are being tested against a standard of military toughness in dealing with Soviet pushiness and Gulf turbulence. The common diagnosis is that the United States has gotten into its current fix by failings of perparedness and will. "Leadership" is seen as the winning or regaining of international respect, especially the Soviet Union's.

Okay. I share some of the common misgivings in this regard. But room has got to be made for another element: Third World military contingencies are problematical and, with luck and sound policy, can be staved off. Third World economic contingencies are relentless and unavoidable. "Leadership" in that sphere can only consist of the tedious, politically debilitating and undramatic work of developing a design that minimizes conflicting interests on both the foreign and domestic side.

The pity of it is that, the campaign apart, so much of the discussion of these issues in recent years has been ideological, abusive and stale. The left has paid court to Third World economic "rights" that have been denounced from the other end of the spectrum as "looting." The old liberal-internationalist commitment to foreign aid has collided with the ingratitude and political nastiness of many of the beneficiaries -- and with their refusal to make OPEC accept its share of the blame for their foundering. Whether the frustrations of backward nations flow from the workings of the international "system" or from their own choices of policy and ideology is endlessly and bitterly debated. Protectionist current run strong.

In this flux, it would seem natural to take the general foreign policy positions of the candidates and to proceed to a judgment of their capacity to handle this particular basket of eels.Thus, Ronald Reagan would be even more of an economic nationalist and hard bargainer than Jimmy Carter who, despite his early disposition to grant the moral high ground to the Third World, ended up in a North-South bargaining posture that left the South's spokesmen dismayed.

But what may count more in the next president is his understanding of how the foreign and domestic economies fit together, and his ability to work with Congress on the political side. Carter seems to me to have more of an evident edge over Reagan in the former quality than the latter. John Anderson perhaps has some promise in both.

John Sewell, president of the Overseas Development Council and an expert witness for pulling together, believes that "through mutually cooperative efforts, the developing countries could become the 'engine' of future world economic growth in the 1980s -- if the industrialized countries are willing to invest in their economies, to extend financing and to buy their products." You may not be that upbeat, but the promise -- the burden -- will be there waiting all the same.