It is important to note that during the Cold War, NATO and the Warsaw Pact were preparing for two entirely different types of nuclear war.
The United States and its allies focused primarily on a strategic war. A strategic nuclear scenario involves a rapid launch of long-range, high-yield weapons that essentially wreck complete havoc on the unfortunate recipient. In such a "war," speed of deployment and survivability during transit were of utmost importance since no one really expected to survive the target's retaliatory strike with much in the way of useable infrastructure. Essentially, the Western Bloc was planning for a nuclear war that consisted of a of single, absolutely devastating salvo of long-range nuclear weapons. Actually, it is now known that we had plans to launch a second, delayed strike that was timed to hit just as our enemies were getting out of their hardened shelters, but no one was banking on any of the equipment still being useable. To this end, NATO devoted most of their funds to intercontinental ballistic missile systems (ICBMs), ballistic missile submarines (boomers), long-range strategic bombers (like the B-52, the B-1B, and the B-2), and megaton-yield warheads.
The Warsaw Pact, on the other hand, was more strongly focused on a tactical war (although they did also have a strategic program). A tactical nuclear war is best described as a conventional war fought with nuclear munitions. While the Americans went about building scores of ICBMs and nuclear warheads, the Russians had all sorts of nuclear deployment devices. They had small, kiloton-yield nuclear artillery shells, nuclear tank shells (the explosive sort, not our depleted-uranium sabot rounds), and nuclear torpedoes. As quoted in an above write-up, nuclear weapons were just another munition. While NATO was planning on a single, cataclysmic exchange, Russia and her allies were preparing to actually slog through a nuclear shooting war.