The question of the day is war, limited war, one fought with limited means for limited ends in the politically punky areas lying between the United States and the Soviet Union.

President Carter says that the United States would use force if necessary to repel "an attempt by any outside force to gain control of the Persian Gulf region." Sen. Edward Kennedy replies that "President Carter may take us to the edge of war in the Persian Gulf. But he will not ask us to end our dependence on oil from the Persian Gulf. I am sure that every American would prefer to sacrifice a little gasoline rather than shedding American blood to defend OPEC pipelines in the Middle East."

Would we, could we, should we fight for oil?

Would we? That's the simplest part. Carter is right, I think, to say he would. Some people may doubt him, but at the least he gives prospective interlopers pause. Kennedy tempts such interlopers with a free ride. He offers a formula that moves too slickly from a fair critique of Carter's inexcusable flabbiness on energy to a dream-world suggestion that in no circumstances need the United States contemplate the hard option of fighting.

Could we fight for oil? Defense Secretary Harold Brown has just conceded that, while the Russians may be planning to field the forces to fight three wars at a time, the United States "never fully acquired the agility and the mobility" to fight the one big and one small war it has been planning for since 1969. As he explains it, "Although, during the past decade, we never acquired all the readiness and mobility required by [our] strategy, we were not penalized for it because our potential enemies were relatively sluggish, and we were not put to the test by contingencies outside of Southeast Asia. But now times are changing."

A gap has opened. Johns Hopkins University's Robert Osgood writes in a sage new study, "Limited War Revisited," between strategic concept and operational power. The concept is that old faithful, containment. At least until Carter's new defense plans bear fruit, however, the power to give confidence that the United States can make containment work is not in evidence.

The United States, writes Osgood, "chastened by losing a war and conscious of the new complexities of coping with Soviet power, is caught between the lessons of Munich and Vietnam. Consequently, although the strategy [of limited war] is more widely accepted than ever, its utility as an instrument of policy where the prospect of local wars and Soviet intervention is greatest has never been more in question. Logically, the United States should either clearly devalue the nature and scope of its security interests . . . or else it should launch a major effort to attain limited-war forces. . . ." Put up or shut up.

Should we go to war for oil? To assemble the forces, bases, allies, etc., is merely to get into a position to choose. The go-go spirit in which limited war was conceived in the John Kennedy period cracked in Vietnam. The never-again mood that then set in over the whole notion of limited war is yielding now to the new anxieties snapped into popular focus by Soviet tanks in Afghanistan.

Right now, as I see it, our debate is poised between left and right, between Kennedy and the Reagan-Connally line, between the idea that using force is the problem and the idea that not using force is the problem.Carter is testing the middle ground.

Osgood offers sensible guidelines:

Limited war should be undertaken only when there is more at stake than national influence and prestige in the name of security.

There should also be at stake -- there were not in Vietnam -- specific goals of substantial intrinsic value from the standpoint of U.S. military and economic security.

The decision to fight should be a matter of "careful analysis, not an automatic inference drawn from historical analogies and doctrinal abstractions."

And everything -- from the durability of a Soviet-supported victory to the U.S. domestic political base -- has to be cranked in.

In sum, make the best case.

Osgood understands that "this process of reasoning [could] be taken as a formula for paralysis." Even as thinking about limited war in the past was short-circuited by conditioned reflexes, so thinking now should not be overloaded with a search for excessive certainty. A balance is there to be struck.