To what extent, and in what ways, do perceptions or beliefs about the relative military strengths of the U.S. and USSR diverge from the calculated "facts" or "realities"? Are beliefs about the "strategic" military balance formed separately from, or jointly with, those about the "conventional" balance? What types of forces affect beliefs about the strategic balance, and with what weights? The author presents four models that define exhaustively, but in simple terms, the range of possible relationships between "perceptions" and "realities" about military balance. These relationships reflect differing hypotheses about the causal connections involved. Several examples and anecdotes are included to illustrate the models. 11 pp.