A highly accurate, multiple independently targeted re-entry vehicle, delivering precision low-yield warheads, is a silo-buster. It is designed to administer a devastating first strike on an enemy's ability to respond to a sneak attack before they have the ability to improvise a counter-strike. MIRV plays no role in deterrence. This is particularly the case when it is launched from existing silos the USSR was well aware of. What were the Russians expected to do? Target the empty holes?

The great cost of diverting funding from hardening our silos and filling enough of them with cheap city-busters in sufficient numbers to survive and then respond to a Soviet attack was enough to telegraph the message loud and clear to the USSR: we had every intention of striking first and didn't give a damn if they knew it. The installation (at great expense) of this technology on our missile submarines (supposedly our last line of defense to punish an attacker who managed to get in the first blow) drove the message home with astonishing clarity. We were going to hit first and hold their cities hostage to their second strike.

Everyone in the industry not indoctrinated by chickenhawk Neocon warmonger ideology or infected by Hermann Kahn's nuclear cowboy fantasies was perfectly aware of this. I was, I worked in the industry at the time, and I briefly worked on two separate intelligence systems designed to frustrate Soviet deterrent strategies, NOT to discourage them from engaging in a pre-emptive strike.

Whatever Soviet retaliation survived the American blitz would be mostly absorbed (hopefully!) by Star Wars, a system we had threatened the Soviets with hellfire about when they toyed with the idea back in the 70s. Remember? We pressured them into signing the ABM treaty with threats and bluster, and then did a one-eighty when it served our purposes to engage in that exact same strategy ourselves. I believe we were closer to nuclear war in the 80s than at any time in our history, even more so than in the Cuban Missile Crisis.

We got lucky. The Soviet Empire collapsed, and I must grudgingly admit, they showed remarkable restraint during their last days. Things have settled down now with the Russians, and the Neocons were eventually totally discredited in the Iraq fiasco, but I wouldn't want to press my luck with the Koreans. Those guys are crazy, and they are desperate. They're not dumb enough to start a war on purpose, but they aren't smart enough to keep one from happening by accident.

The same might be said about us.