Twice within the last two weeks, three times within seven months, a false alarm triggered the warning system of our strategic nuclear forces. Judging from published reports, computers indicated that Soviet missiles had been launched against the United States and, in accordance with prearranged procedures, our strategic forces went through the first stage of an alert.

No one was hurt, no damage was done. Harmless incidents? Or are we walking on thin ice and seeing how readily it can crack?

Mankind has suffered from many wars that were launched without much thought and purpose -- launched as if by accident. The sequence of rash decisions in 1914, following the assassination of the Austrian archduke, had obviously not been planned by any of the powers that it dragged into World War I. But the nuclear missile age has burdened mankind with a more acute, a far more formidable risk of accidental war. The risk is inherent in the global interlock of armaments capable of inflicting cataclysmic destruction and designed to be committed to war irrevocably, within minutes.

How can we be sure that, for decades to come, a technical malfunction or some human error, or a combination of both, will never trigger a salvo of nuclear missiles? Substantial progress has been made during the last two decades in the design of clever and redundant safeguards for our nuclear weapons and missiles. Despite some bureaucratic resistance and inexcusable sluggishness, these safeguards have been put into effect to an increasing extent. Perhaps that's why we are still here.

However, in recent years, a combination of corrosive forces has been at work to increase, in hidden and insidious ways, the risk of accidental nuclear war. Among them are the relative decline in our strategic power, the unimaginative pursuit of arms control concepts after events have long overtaken them and -- the inevitable accompaniment -- deceitful political posturing that tries to conceal fundamental weaknesses.

Beginning in the 1960s, we sought to avert a nuclear arms race, with its feared instabilities, by hobbling our own strategic forces through self-restraint and by attempting to limit the growing Soviet forces through strategic arms control. The former was mightly effective; the latter, alas, was not. Soviet missile forces grew much more than ours and will continue to do so in the early 1980s, with or without the new SALT II agreement. As a result, our deterrent forces will become increasingly vulnerable to a preemptive strike. The balance of terror is becoming less stable.

Despite this disappointing failure of SALT process, President Carter called the new SALT treaty (yet unratified) "a major accomplishment of my administration."

In planning our strategic forces for the dangerous 1980s, the administration now uses the SALT agreements and SALT concepts as the map for the future. Yet many of these concepts, inherited from the 1960s, have proved to be harmful to strategic stability. The sad truth is they tend to increase the risk of nuclear war.

For example, SALT compels the United States (and perhaps the Soviet Union) to deploy a smaller number of large missiles rather than a large number of small ones, thus concentrating the targets for a surprise attack. Similarly, SALT not tends to impair the mobility of landbased missiles, thus increasing their vulnerability. And SALT generously tolerates ballistic missiles -- the main cause of strategic instability -- but is intolerant toward cruise missiles even though they are too slow for a surprise attack.

If we continue on the present course -- without a sustained effort to reverse the strategic deterioration -- the temptation will grow to reach for desperate remedies. Last year, in his annual report to Congress, Defense Secretary Harold Brown raised the curtain on such a remedy. He pointed out that the Soviets "would have to consider the possibility of our having launched" our missiles before theirs arrived. And in this year's report to Congress, the idea is repeated. Prudently, Secretary Brown adds that "we would by no means wish to rely on having to" use such a tactic. But from the context of this statement it is clear that the notion of a "launch-on-warning"" possibility is supposed to be reassuring.

"Launch-on-warning," as a remedy for the growing vulnerability of our land-based deterrent forces, is an idea that attracts strange bed-fellows. Some shallow super-hawks have liked it as a sign of our quick-on-the-draw toughness. Equally shallow arms control advocates (in and out of government) have promoted it as a way of defending SALT against critics who worry about the deteriorating strategic trends. And the defense budget cutters find it irresistible; it is the cheapest "fix for the strategic vulnerability problem.

But the cure is more deadly than the disease. The more we rely on "launch-on-warning" (or, for that matter, the more the Soviets do), the greater the risk of accidental nuclear war. Anyone who tries to explain that this tactic could be implemented in a totally reliable and safe way is a fool. He does not even know how little he knows. No one can understand in sufficient detail all the possible malfunctions, unanticipated events and human errors that might interact someday to confound the "redundant" warning systems or to bypass the "safeguards" against an unintended release of the command to launch a missile salvo.

The crux of the matter is that the more important it becomes to "launch on warning," the more dangerous it will be. The tightening noose around our neck is the requirement for speed. The more certain one wants to be that our missile forces could be launched within minutes and under all circumstances, the more one has both to practice the system and to loosen the safeguards. And remember: as in June 1980, there will be false alerts.

The dilemma is similar to that President Carter faced in ordering the raid to rescue our hostages in Iran. Leaning toward caution, using too few helicopters and setting up multiple opportunities for bail-outs condemned the raid to a "false" attempt. But leaning toward boldness might have dragged us into a war where our inferior military power could not have succeeded.

In the State of the Union message, Carter proclaimed that any attempt to gain control of the Persian Gulf regio will be repelled "by any means necessary, including military forces." Six days later, he admitted that we did not have enough military strength to defend the region unilaterally. But President Carter has not forged new alliances recently. He has, however, strenuously urged Congress not to increase the defense budget.

We should not have to rely on launching our missiles in response to fitful warning signals. We should not provoke our adversaries by hollow gestures; we should not rush forward to extend military protection by oratory and fail to back it up with real strength; we must not manifest trigger-happiness to conceal weakness.

We cannot move toward a stable peace if we pursue a defense policy that permits a continuing deterioration in the military balance but -- as if to compensate -- creates a growing risk of a war by accident. Even if wrapped in various SALT treaties, such a policy cannot lessen hostility between our country and the Soviet Union. Indeed, in the most fundamental sense, such a policy is incredibly hostile. It neither rewards peaceful behavior nor punishes aggression; from the point of view of the Soviet Union, it simply poses as an uncontrollable lethal threat.