RICHARD LOWENTHAL
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SALT agreement, while imperfect, became the core of the policy of
detente, of which the Ostpolitik of the German Federal Republic
came to be a part. Instead of the former American nuclear superior–
ity, the apparent stability of the nuclear balance now continued ef–
fectively to deter a nuclear war; together with the new general cli–
mate of East-West detente, it became a new reason for West Ger–
man equanimity. In that climate, German opinion overlooked the
fact that another aspect of the situation had changed: in a situation
of nuclear balance between the United States and Russia, the
credibility of "extended deterrence" of
conventional
attacks had clearly
diminished.
From the middle of the 1970s, however, as negotiations about
SALT II proceeded, the stability of the strategic nuclear balance
began to appear doubtful, while the regional nuclear balance in Eur–
ope was clearly upset by the Soviet development of the SS 20. From
the West German point of view, acceptance of the new situation in
the absence of fully credible "extended deterrence" meant becoming
open to nuclear blackmail. However, stationing corresponding
United States weapons in Western Europe, including Western Ger–
many, would not only increase the credibility of "extended deter–
rence," but might also carry the risk of a nuclear arms race in a situa–
tion of unstable balance - a situation that had never before existed.
NATO's "double-track" decision of December 1979, urged by the
West Europeans, including the West German government of Helmut
Schmidt, was an effort to avoid both dangers by convincing the So–
viets that their superiority in the European nuclear balance would
not be tolerated, but that an arms race could still be avoided by
agreeing on a stable balance in that theater.
Yet from the moment that the threat of the SS 20s had become
obvious, the threat of a nuclear arms race in an unstable balance was
bound to remain until an agreement on a stable balance was reached.
At the same time, the sense of reduced credibility of United States
"extended deterrence" was also bound to remain, pending the sta–
tioning of United States intermediate-range missiles in Europe. But
a nuclear arms race in an unstable situation implies a temptation for
either side to attempt a nuclear first strike when it feels temporarily
superior but is afraid the situation might be reversed tomorrow. Ow–
ing to the improbability of either side becoming sufficiently superior
to the other for an annihilating first strike, and to the necessary
uncertainty of each side's estimates of the strength of its opponent, it
