"We want no Euroshima." The phrase has become a popular slogan for the European peace movement that is mobilizing an autumn campaign of mass rallies, sit-ins and blockades to halt the planned deployment of Pershing II and cruise nuclear missiles beginning this December.

While the peace crusaders may not block the stationing of modern middle-range rockets--set to take place unless a surprise accord is reached in the Geneva arms talks--they already have succeeded in stirring up so much public alarm about excessive reliance on nuclear deterrence that the North Atlantic Treaty Organization is exploring other strategies.

The issues of how high to raise the threshold of using nuclear weapons to stop an attack by the Warsaw Pact is developing into the most sensitive military debate of the decade for NATO.

Gen. Bernard Rogers, NATO's supreme military commander, has said European forces could not last much more than seven to 10 days against a full-scale assault from the East. Faced with the prospect of a complete rout, he would be forced to ask permission to use nuclear weapons in the early stages of battle, he said.

Rogers said that if European governments want to relieve public anxieties by raising the threshold for using nuclear weapons, they will have to spend more money on modern conventional weapons that can strike deep behind East Bloc lines to disrupt supply and communications channels.

Only by taking advantage of the West's superiority in high technology, he said, can the alliance rest secure knowing that it could thwart a Warsaw Pact assault by knocking out second echelon reinforcements that are crucial to a sustained Soviet-led assault.

Rogers has called for a 4 percent yearly increase in military spending, after inflation, through the rest of the decade to finance an impressive array of laser-guided missiles and antitank aircraft that he wants to include in the NATO arsenal.

This "insurance premium," he calculated, works out to an average of $23 a year for every man, woman and child in the nations of the alliance.

By upgrading western defenses in such a manner, Rogers contended that the Soviet Union would then have to bear the burden of escalating any attack by deploying nuclear weapons.

He does not, however, advocate that NATO adopt a "no first use" doctrine in nuclear weapons because he wants to keep that risk uppermost in the minds of Soviet military planners.

Rogers' plan has aroused skepticism in European capitals, chiefly because governments fear that its cost could spiral out of control and also undermine, in the public mind at least, the rationale for nuclear missiles.

A British military planner at NATO criticized the strategy as "too modest and too ambitious." It does not manage to eliminate the central role played by nuclear weapons in western defense, he said, and at the same time requires NATO governments to meet a spending goal beyond the current 3 percent goal that most of them have failed to achieve.

Other European defense strategists point out that such a scheme involving deep attacks in East Bloc territory would effectively shift NATO military thinking from defensive concepts to attack-oriented aims.

More important, they said that such a transformation carried the risk of forcing the Soviet Union to adopt a more hair-trigger defense posture if the West acquired the capability of fast and accurate attacks on Warsaw Pact targets.

Moscow could feel compelled to move forward its own missile systems into East European countries, a step that also would require greater military presence and thus a more domineering role in East Bloc affairs.

Besides the additional costs and retaliatory action it might provoke by Soviet military planners, the Rogers plan has been criticized by West German officials for complicating the public debate in their country over the necessity of deploying Pershing II ballistic nuclear missiles later this year.

"If you start talking about raising the nuclear threshold so high you will not need to use nuclear weapons, people ask why you need them at all," said a West German defense planner.

"For us, either kind of conflict, nuclear or conventional, means total destruction. Therefore, we want to keep the Soviets acutely aware that any attack could risk a nuclear war that could harm them as much as us."

West German Defense Minister Manfred Woerner insisted in a Bundestag security debate recently that nuclear weapons have helped maintain peace, largely because the Soviets realize that any military action against the West risks the possibility of nuclear conflict.

Bonn officials say that transferring too much emphasis to a conventional deterrent could tempt Moscow into thinking that it could launch a limited assault, without serious dangers of either side deploying nuclear weapons.

To forestall that possibility, a NATO policy planner remarked, the alliance doctrine of flexible response "has always been to walk that fine line between perceived strength and vulnerability."

While the Rogers plan seems condemned for the moment since the NATO allies appear unable to meet the spending requirements, the gradual implementation of some of his concepts seems inevitable as NATO incorporates new generations of weapons such as the Per an era of increasingly fast, accurate and more devastating weapons systems, as a European defense planner at NATO headquarters said, "there is going to be a dangerously small margin between the controlled and uncontrolled hostility."