"Eventually the footing would become materially more secure

 through the emergence of a military-industrial complex devoted to perpetual growth (and hence also to the idea of a perpetual threat). But at the outset it was necessary to simplify matters for Congress and the public. The Soviet Union was thus identified with Nazi expansionism by means of the category of totalitarianism. This deliberately scary vision culminated in a familiar exhortation to chose righteousness in the face of historical fate. A satanic force, dedicated to the overthrow of every sound and proven American principle, was abroad in the world, most frighteningly even at home through its fifth columns. To refrain from doing one's utmost to extinguish this evil was tantamount to sin and would end in self-destruction. The choice was plain. Only the United States could perform the given task. Would it rise to the occasion and do its appointed duty? And so forth.

-Manifest Destiny: American Expansion and the Empire of Right by Anders Stephanson, pg. 124