The next phase for the US nuclear deterrent has been held up now for nearly three years for one simple reason. The proposals which came out of the Pentagon failed to sound like common sense to the laymen in Congress.
The new proposals which came out on Monday of this week from a bipartisan presidential commission have an excellent chance of being accepted by Congress (and thus of getting the deterrent program going again), for the simple reason that they sound like common sense.
One reason they sound like sense is because the commission and its panel of senior counselors included several seasoned politicians as well as a number of Democrats. This was not a cluster of generals and admirals making up a Santa Claus wish list for the Pentagon.
It included three Republican former secretaries of defense, Melvin Laird, Donald Rumsfeld, and James Schlesinger. Democrats included Harold Brown, who was Jimmy Carter's secretary of defense, and Lloyd Cutler, a leading Washington lawyer usually consulted (sometimes too late) by Democrats in any kind of trouble.
The average Democrat in Congress will have confidence in a program which has been marked approved by both Harold Brown and Lloyd Cutler.
Pre-Reagan Republicans are likely to be impressed by a program which has been approved by men who worked under Richard Nixon and Gerald Ford.
The group was bipartisan in the double sense that it included Democrats, Republicans, and also pre-Reagan Republicans.
It was sensible to set it up that way. It took the decision on strategic weapons out of the political arena. And the men who were so prudently selected were also prudent in their proposals. They did not make a single proposal which is going to seem wild or woolly or irrational to a layman in such matters.
The original Pentagon proposal when Mr. Carter was President got itself blown out of the water on grounds of plausibility. That plan, nicknamed ''the race track,'' called for paving vast areas of Western desert with concrete highways and building, also at vast expense, a series of shelters or launching pads which could be closed over.
The idea was to trundle the big, 100-ton MX missiles around the race track from one pad to another at night, letting the Soviets guess which cover concealed the missile. The proposal overlooked the fact that the Mormons who largely own and politically control Utah, and some of Nevada, did not like the idea of their homeland being paved over and covered up - and thus inviting Soviet attention.
It was political stupidity to propose a plan for Utah and Nevada which would not be acceptable to the Mormons.
Next came the ''dense pack'' under Mr. Reagan.
The more the Congress heard about ''dense pack'' the less plausible it sounded. No matter how sensible the experts said it was, it didn't make sense to a nonexpert.
One more idea like that would have meant the end of MX.
So what are we offered now?
The bipartisan commission thinks that building 100 of the new MX missiles, which can soon be ready for deployment, makes some interim sense. They are designed to fit into the silos which now house Minuteman missiles. So put them into existing silos. No new silos need to be built. That saves something like $5 billion over the next four or five years.
But everyone knows that with the increasing accuracy of the new generation of missiles the fixed silo is becoming increasingly vulnerable. The best way to reduce vulnerability is to make the missile mobile. So the commission proposes an immediate research and development program aimed at perfecting an entirely new generation of mobile missiles.
The goal for the ''R and D'' people is to be a missile of only 15 tons with a single, but highly accurate, warhead. They want this new weapon to be ready for deployment in the early part of the next decade. They figure on ten years to get it operational. They propose that the US immediately start talking to the Soviets with the purpose of getting new agreements. They think that single-warhead weapons will make for easier negotiations, not harder.
They believe that single-warhead missiles which are mobile and hence less vulnerable mean greater security, and greater stability. Hence they think that, if the Soviets would also go in that direction, the chances for limiting the numbers and sizes would improve.
It all sounds good to the laymen. The Pentagon may dislike it, but smaller weapons which are less expensive and less vulnerable and could make an agreement (in theory) easier with the Soviets are just what is needed - if Congress is to approve of any MXs at all. Sensible and experienced politicians helped to draft this plan - and its presentation.