It's been more than two days now, and we're still waiting for the "storm of protest" some reports predicted after President Reagan's decision to assemble the neutron bomb. It's true that the ever-holy Scandinavians are protesting, and the Soviet Union's Tass news agency, as expected, called it an "extremely dangerous step." But the distinguishing feature of the reaction from West Germany, Britain, France and other European allies is that it has been muted.

In some ways this is not surprising. The bomb always made sense. It puts out the same sort of lethal radiation any other atomic weapon creates but much less blast. So it can be used in certain tactical situations in which other nuclear weapons would be too destructive. One such would be against massed armor concentrations of the sort the Soviets are likely to send into battle should they move against the heart of Europe. . . .

The critics of this decision are griping not so much about substance as about timing. They worry that unilateral U.S. decisions will undermine European support for the planned deployment of medium-range missiles in Europe in 1983. There certainly is reason to hope that the Europeans' pledge to accept these missiles proves sturdier than their earlier pledge to increase defense spending by 3 percent a year in real terms. But the deployment, in any case inadequate to offset what the Soviets are already doing, is certainly no reason to Stop American defense plans in their tracks.

We have not had much luck encouraging greater defense effort in Europe by playing to the fears of its admittedly substantial pacifist, leftist and communist sentiments. The alternative is to confront the Europeans with a choice. Mr. Reagan has promised a full consultation with them before deploying the weapons in their countries. Our bet is that he will be on far stronger ground in any such consultation with the neutron weapons screwed together than he would be with the parts stored in separate warehouses.

What Mr. Reagan has done here is to correct a wholly wrong and enormously damaging decision by his predecessor. Naturally the earlier mistakes and the Soviet propaganda offensive have loaded the decision with emotion. Some may call it insensitivity, or somesuch, to do the right thing in these circumstances. We call it leadership.