ABOARD THE USS AMERICA, Under Way -- It is 11 p.m. Do you know where your children are? Some parents' children (well, almost children: the crew's average age is barely 20), are launching, recovering, refueling, rearming and repairing high performance aircraft in a small space, smoothly, on an 82,000-ton air base that can move hundreds of miles in a day, its screws churning up a 40-foot rooster tail or spray aft when at top speed.

Nowhere on Earth are so many complicated actions, involving so many forces and energies, and requiring so much mechanical agility and allowing so small a margin for error, performed with such ,elan as on a carrier. It is a carefully choreographed ballet, with noise and danger all around. It is a performance appropriate to, and vital in, an era of violent peace.

The Soviet Union is a self-sufficient land power in minerals and energy, with no defensive need for the enormous navy it is building. The Soviets have offense in mind and have three times as many ships as the United States -- more conventional and nuclear submarines, more cruisers, more destroyers. The U.S. advantage is its carriers, 14 to three. Last year a single Soviet exercise involved 200 ships, including 70 submarines. The Soviet Pacific fleet alone has 575 ships, including 134 submarines. Consider those numbers when hearing complaints about U.S. plans for a 600-ship Navy by 1989 (up from 479 in 1980).

For the United States, with 40 treaty undertakings, commercial dependencies and global power responsibilities, naval superiority is a necessity. In the last 40 years, presidents have maneuvered or otherwise used forward-deployed Navy and Marine units 250 times to further policy objectives. And today the West lacks the merchant tonnage to sustain heavy losses in a submarine war of attrition as in World War II. (Hitler nearly won the war in 1942 with about 60 operational submarines. The Soviets have nearly 300 attack submarines.) Thus the United States needs a "forward strategy" to engage the enemy closer to his border than ours. Carriers, with their young crews of more than 5,000, are the key to that.

The armed forces run the nation's best job- training program for entry-level, often minority young people. At a recent ceremony on the carrier Saratoga, more than 400 sailors received high-school diplomas. When young men who work on carrier flight decks leave for civilian life, they can be reasonably certain that they have had the hardest job they will ever have. They will leave with something priceless: self-esteem. Of course, many will not leave. Last year 58 percent of first-term enlistees reaching the end of their commitments reenlisted.

On a normal day last year, half of all sailors were assigned to sea duty, and one-third of the Navy was under way. The Navy often does not seem to know the reduced tempo of garrison life. For the crew of a submarine on patrol, or a carrier cruising for 100 days without a port of call in the steamy Indian Ocean, there is nothing to do -- nothing, except work, constantly. As one of this ship's officers puts it, laconically, during a nonstop 40-hour exercise: The main difference between life on a carrier when in its normal training and life on a carrier in a conflict is that in conflict "fewer planes would be coming back."

You cannot pay people to land high-performance aircraft on a carrier at night. That is, you cannot pay enough to get people to do that unless they enjoy it. But you can pay them too little -- so little that the demoralizing sense of national indifference erodes resistance to the temptation of the rewards that are always there for the taking in civilian aviation.

Congress can save a few million dollars by practicing false economy at the expense of aviators' reenlistment bonuses. But morale, and not just of pilots, varies with compensation because compensation is the tangible sign of an intangible: society's gratitude for hard work performed beyond the horizon. If the experience level of the pilot corps declines, and if the morale of the entire support crew declines, as it did in the 1970s, a predictable result will be an increase in the crashes of aircraft costing far more than an effective program of small but effective bonuses.

It may seem paradoxical, but it is the plainest truth: The more complex the military organization and the more sophisticated the technology, the more the success of the system depends on morale. Success depends on the concentration and zest and sweat of the most complicated and variable of military variables, the men and women who put their hands on the metal.

The disconcerting aspect of a visit to a carrier is the intensity of the gratitude of the crew for any civlian attention to what they are doing. The gratitude is flowing in the wrong direction.