Supercargo: ABMs are no match for multi-head missiles.

As currently deployed, you are correct. However, it will force Russia to use multi-head missiles for every attack, and the better Star Wars gets (with lasers supplementing ABMs), the more warheads Russia must use on each MIRV. Every incremental improvement in missile defense brings us closer to the day when the number of indepedently-targeted warheads on each ICBM required to penetrate the shield exceeds the payload capacity of even your largest rocket.

During the Reagan years, Soviet generals would make periodic threats to launch-on-warning.

That’s the difference between the US and the SU: Civilians are in charge of our military and they get to make all the threats, not the generals. But if the US gets attacked, the excuse that it was a rogue general won’t cut it. We’ll hit back with disproportionate force. And if the attack is nuclear, a disproportionate response would be unthinkably devastating.