The White House knew that President Reagan's decision to produce and stockpile neutron weapons would create controversy in Western Europe. It announced it anyway, and in the process raised a question:

Does the United States intend to deal less gently than before with its NATO allies?

Interviews with administration officials in recent days indicate, however, that the decision was not meant to challenge allied governments, even though many of them would have preferred that it be postponed. Nor was it in reaction to the West German government's recent indication it would not increase defense spending as much as previously planned.

Senior White House aides say they never doubted the president would give the go-ahead to neutron weapons. Before, during and after the election, Reagan criticized President Carter's vacillation on the issue and ultimate failure to go ahead with the new weapons in 1978. Aides point out that Reagan's public statements on the neutron weapon, as on many issues, continue to serve as a pretty good road map to his intentions.

But the decision is, nevertheless, an important event in U.S.-European relations, officials explain, in the sense that it demonstrates that the Reagan White House will take actions it considers important, especially in the security field, even when these are likely to be unpopular within the alliance.

Other officials suggest that the unilateral American decision to build the weapons is also a return to more traditional U.S. decision-making as it was carried out before the Carter administration.

In this view, European governments -- always under pressure from left-wing and other antinuclear groups -- would much prefer for political reasons not to have to signal their acceptance of these controversial weapons before an American president makes the decision to build them. This suggests that allied leaders may be grateful for the president's unilateral action. In part, Carter's decision not to deploy the neutron weapons, after indicating he was likely to do so, came about because the Europeans failed to give any clear public endorsement of them.

At the same time, the anti-neutron reaction in Europe -- protests, demonstrations, harsh political commentaries -- has thus far been rather subdued, in the view of officials keeping track of such things. What this may mean, some officials speculate, is that there actually is more opportunity for American initiatives or leadership in Europe, where the tendency in recent years has been to be critical of many U.S. actions, than was previously thought possible.

There are other reasons why the initial reaction may have been muted.

The Reagan plan, unlike earlier proposals, involves stockpiling the weapons here rather than deploying them to Europe. The idea would be to airlift them to Europe in a crisis and only after consultations with allied governments. It is reasoned that in a crisis, the allies may be more receptive to having such weapons on their soil. The neutron weapons are primarily artillery shells, so they can basically be moved in secret without raising public attention.

Another reason for the relative lack of protest thus far is that August is Europe's traditional vacation month when bureaucrats, editorial writers and demonstrators alike tend to head for the countryside. "For anybody who knows Europe," one administration official said, "August is a pretty good month to do something that the Europeans will find awkward."

Officials claim there were good policy, technical and cost reasons for making the decision now. But they acknowledge that the August vacation time was also a factor in the timing and announcement of the decision because of the importance of public reaction.

Indeed, public opinion was a key factor in the internal deliberations of the administration on the neutron weapons. There was general agreement such weapons would be militarily useful against the massed tank armies U.S. planners see the Soviets mustering. Because they rely more on radiation than blast, the neutron weapons, at the same time, could be fired at less cost to nearby civilian areas or allied infantry.

This is their military virtue; it is also their vice from the standpoint of antinuclear groups, who think they make nuclear warfare more likely.

The crucial question, however, was whether a decision on production of the neutron weapons at this time would endanger a possibly more important, also controversial NATO plan to deploy U.S.-built cruise and Pershing II missiles in West Germany, Italy, England and possibly Belgium and the Netherlands.

Secretary of State Alexander M. Haig Jr. argued for delay, according to administration officials, based on several factors. Haig argued that another six months or so would provide more time to work on the Dutch and Belgians, who have continued to hold out against even the cruise missile deployment. The Italian government, Haig added, was just about to announce that it would deploy cruise missiles in Sicily, a decision that would also be controversial there and would perhaps be exacerbated by a U.S. neutron announcement so soon.

Delay would also allow more time to work on European public opinion, by such means as release of heretofore secret intelligence data on the Soviet SS20 intermediate-range missile to help convince the Europeans that the U.S. missile decisions were necessary. And delay would have moved back the neutron announcement until after Haig's scheduled meeting in September with Soviet Foreign Minister Andrei Gromyko, an event which could also be used to convince Europeans that the Reagan administration was serious about arms control talks with Moscow.

Reagan, however, was more persuaded by the arguments of Defense Secretary Caspar W. Weinberger that the hardware and optimum production schedule were at hand, that it would be costly to delay, that a clear, unilateral decision would demonstrate decisive American leadership and commitment to military improvements and, in a way, take the Europeans off the hook.

It was also argued that there would never be a "good time" when criticism was not to be expected. "If we sit here and say 'We can't do this because if we do the Europeans will'. . . and then you just fill in the blank, that will always provide an excuse not to do something," a top administration official said.

Officials said that within the Pentagon, the military high command and the White House, there were some who were annoyed by European criticism of the United States rather than the Soviet Union, while Moscow had troops in Afghanistan and around Poland, and who did feel "it was time the make the Europeans feel uncomfortable."

But these officials said that there was no anti-European feeling evident from Reagan or his top aides and that the neutron decision was not meant to "stick it in the ear" of the allies.