Poses two questions: How can we explain the monotonic growth of the Soviet military budget over two decades when overall economic growth was slowing down? Can changes in this pattern be expected? Section II defines and analyzes the concept of the Soviet defense burden, then surveys empirical measures of the burden. Section III is skeptical about the extent to which the Soviet buildup is a response to external threats to security. The persistent buildup is seen instead to reflect the leadership's perception of national priorities and to be supported by a decisionmaking apparatus that maintains them. In the near future, external challenges (particularly the U.S. buildup) and opportunities will create pressures to maintain the pace of military spending, but worsening economic prospects will make it increasingly burdensome. Neither Brezhnev nor his successors is likely to have new options for dealing with this dilemma, and considerations that have induced the Politburo to try to "muddle through" will probably continue to dominate. U.S. policy has a significant capacity to influence Soviet policy in this direction.