Last week, in the afterglow of the Reagan administration's admission that, yes, it had decided to assemble the neutron bomb, I plugged my ears and fortified myself against impending distempers.

You will recall that the Pericles of Plains, Ga., had decided to leave the neutron bomb in pieces so as not to arouse the successors to Bertrand Russell and Nikita Khrushchev. Well, now, according to Washington's cognoscenti, Bertie Russellism has converted even the leaders of our NATO allies, who, so the wise ones insisted, favored a NATO deterrent force unassembled and unusable. Ron had really stepped into it this time, and so I joined my fellow Americans in waiting for the diplomatic crisis. Yet Ron still walks with the gods. Europe took his decision calmly. In Paris, one heard mild applause, and in most of the other European capitalss about all that could be heard was the sound of revving automobiles as the eminent joined their countrymen in heading for the beach.

The only noticeable squawks came from the same old hen houses: those situated in Scandinavia, the Union of Soviet Socialist Republics and various left-wing haunts here and abroad. Of the aforementioned squawkers, our Soviet friends have the most to squawk about. They now have more than 40,000 tanks ready to bring proletarian revolution to Western Europe. Were war to ignite between the Soviets and the West, these tanks would blitzkrieg across the European plain with devastating force. Unless NATO resorted to tactical nuclear weapons, many analysts fear that these tanks would roll up to the English Channel in a matter of days. In their wake would be destruction, death and the KGB. So much for Europe.

But tactical nuclear weapons are ferociously destructive, and concentrating their destructive force on a specific target is impossible. Once set off, these weapons indiscriminately destroy buildings and lives, both civilian and military. The prospect of using them in Europe has caused anxiety within the NATO alliance for years, much to the joy of Soviet strategists, whose growing armored force increases that anxiety still more.

Now along come those inventive Yanks with a tactical nuclear weapon that can be hurled at oncoming tanks, killing only their crews and infantry support and leaving nearby civilian populations and buildings intact. It is all very good news for those who want to see Europeans freed from the disabling fear of an imminent Soviet invasion and from the enervating pessimism that has so recently haunted their foreign policies. It is also good news for those who admire European architecture, and for those who deal in the used tank market.

Yes, the Soviets are irate, and they have every reason to be. They have spent a lot of very dear rubles on that tank force of theirs, but what good will it be if its crews are certain to be turned into terminal cases as soon as they cross into Western Europe? Let us try to look at the neutron bomb from the Soviet Union's point of view. A war that only kills soldiers? What kind of a war is that? The Politburo's favorite human beings are soldiers. A war that does not destroy nearby villages? When the Red Army goes into battle, it relishes the destruction of villages. Any Afghan peasant will tell you that. For that matter, when the Red Army mixes it up, the primary objective seems to be not victory but the utmost slaughter and destruction. Not only are villages laid waste, but whole cities and countries, too, to better raise up a new order in the image and likeness of Dr. Marx and to give Soviet commanders a sense of achievement. The neutron bomb does not merely threaten the mammoth Soviet tank force; it also takes the fun out of the Soviet style of battle. Neutron warfare is sissy warfare.

Contrary to the neutron bomb's critics, who insist that the bomb will dangerously disturb the balance of forces in Europe, the bomb will help to re-es tablish that balance and in a very benign way. It puts up a fence against potential invaders, while adding very little to the West's offensive capability. Offensive war is what the friends of peace should oppose most staunchly. We must be most concerned about the huge SS20 missiles that the Soviets have targeted on Western Europe, and the Pershing and cruise missiles with which we plan to counter them. Let us seriously negotiate the removal of these monsters. As for the neutron bomb, remember the poesy of Robert Frost: good fences make good neighbors.