Bonn — The West German Roman Catholic Bishops' Conference issued a statement on April 27 that condemns the use of nuclear weapons - but tolerates the threat of use as a powerful war preventive at the present time.
The West German Catholic hierarchy thus joins West German evangelical (mainstream Protestant) churches in a traditional but very troubled view of moral issues in an age of weapons of mass destruction. But its statement is not so radical as drafts of the forthcoming statement from American Catholic bishops.
It says the threat of holocaust in nuclear deterrence is not a legitimate basis for peace ''in the long term.'' But it does not specify how long the short term - in which a deterrent nuclear threat is permissible - might last.
A key measure of the bishops' position is the issue of possible first use of nuclear weapons - an essential premise in NATO's defense posture against a conventionally superior Warsaw Pact. The West German bishops do not state their position directly, but imply that a limited Western nuclear response to a Warsaw Pact conventional attack might be justifiable under certain conditions.
This point was the object of much controversy during the drafting of the bishops' statement. The antinuclear movement in Northern Europe has been primarily a Protestant phenomenon, and rejection of any first use of nuclear weapons is much more widespread among Protestant pastors than among Catholic clergymen here. But such sentiment has been growing in Catholic circles.
The bishops' statement also avoids any judgment on the morality or advisability of the most immediate policy issue: stationing new NATO missiles in Western Europe beginning this December if there is no prior American-Soviet agreement on Euromissile arms control.
Basically, the bishops' statement establishes general criteria for evaluating nuclear policies. It focuses on deterrence - war prevention - rather than issues of war and weapons use as such. It tolerates nuclear weapons as long as possessors seek balance, not nuclear superiority; keep stocks of the weapons as low as possible; and make strenuous efforts at mutually agreed arms limitations.
In this context the bishops see fears of an uncontrollable nuclear war as contributing to deterrence also of a conventional war, which would itself - given today's ''conventional'' weapons - lead to unimaginable devastation. But they acknowledge the ''immense tension'' in tolerating nuclear deterrents, since deterrence is credible only if there is a real threat of use of these weapons.