Cruise missiles: stealing a march or buying trouble?

Public and congressional reaction to the Reagan administration's new five-part strategic package has centered on the MX missile and the B-1 bomber. Paradoxically, this attention may be at once both misplaced and legitimate. It may reflect the uneasy sense that these are but trimmer, racier (and costlier) versions of nuclear weapons delivery vehicles that are or will become obsolete in the 1980s.

What the Congress and the public do not yet see is that the dominant strategic technology of this decade could well be the widely ignored cruise missile, especially the sea-launched version. And the administration seems to know this.

As it cuts back the projected MX deployment by at least half and chooses a cheaper but still vulnerable basing mode for its deployment, the administration is rapidly increasing its planned purchase of the sea-launched cruise missile (SLCM, which may also stand for submarine-launched cruise missile). Planned procurement of this versatile weapon - to which the Carter administration made no commitment - has risen steadily in the short Reagan incumbency from 447 missiles by 1986 to 2,527 by 1989. The eventual buy will likely be much greater.

Navy Secretary John Lehman visualizes that multipurpose cruise as a weapon that can attack a variety of Soviet targets (airfields, depots, railheads, etc.) in attacks following up an initial nuclear exchange. Such missions lend credibility to the view that the administration's strategic program is geared to fighting a protracted nuclear war, for which purpose the cruise is in many ways better suited than other nuclear weapons.

Why is the torpedo-size SLCM so attractive? First, it is in itself inexpensive compared to other systems and its launch equipment and life-cycle operating costs will be far less than those associated with Goliath weapons like bombers or land-and sea-based intercontinental ballistic missiles. (Ballistic missiles follow a parabolic trajectory similar to an artillery shell's but the cruise missile can maneuver and hug the terrain like a manned aircraft.)

Second, though the USSR and the US both deployed cruise missiles over two decades ago, the new American version is so vastly improved that it represents virtually a new weapon. And the US has a commanding lead in this new cruise technology. So, maximizing investment in this area allows the administration to pull a rabbit out of the hat in order to steal yet another technological march on the Soviets. And the cruise has few, if any, of the pencil-and-paper vulnerabilities attributed to land-based rockets or heavy bombers.

Lastly, cruise missiles - small, concealable, and reloadable - are likely to become a nightmare for military surveillance and arms control verification. Hence, maximizing their deployment would end-run both Soviet strategic momentum and the arms control process - an outcome presumably highly valued by many in the adminstration.

Even erstwhile proponents of nuclear arms reduction in Congress and elsewhere have missed the significance of the cruise. Concentrating on the big-ticket items like MX and B-1 and reasoning in parochial Western strategic terms, they often regard sea-launched cruise missiles as preferable to the dinosaur weapons on cost grounds. Or they claim the cruise will not be viewed by the Soviets as ''provocative'' because it is slower to reach targets than ballistic missiles and thus cannot be an effective first-strike weapon.

Much is overlooked in this analysis. Future refinements of the cruise are already on the drawing board and include multiple warheads, terminal supersonic speeds, and the Advanced Strategic Air-Launched Missile. Besides, Soviet military analysts look beyond first strikes to second and third attacks, in which numerous air-or sea-launched cruise missiles with warheads up to 300 kilotons apiece would be devastatingly destructive of the residual capacity to protect borders, preserve internal control, and maintain a war effort.

Morever, there is next to no hope of diminishing the effect of these cruise missile follow-up attacks by precision blows in a first strike. They will be too numerous, too dispersed, too mobile, and too hard to find.

It would be tragic if, in also trying to cut defense costs, those most favorable to deep arms reduction (including, nominally, the administration) gave greater impetus to a weapon likely to preclude any progress on this urgent task.

Finally, amd most important, it is unimaginable that the Soviet Union will not seek some means of overtaking or offsetting this US move. Though it has shown no great interest so far in upgrading its old-fashioned cruise missiles, it has or can acquire the technology base. And the crucial political symbolism of nuclear parity will probably require that the USSR avoid the perception it has been upstaged technologically or numerically by the new American cruise missile. The impact which advanced Soviet cruise missiles on submarine and surface vessels roaming our long and vulnerable coasts will have on American security and our sense of security is something we need only continue on our present course to learn. It is hard to believe the effect will benign.