Not cheap. But likely pretty reliable.
Perhaps without the Russian villains the system has atrophied. Stories like that make me think it can work, but perhaps require a bit more wherewithal to maintain it.
Hell, maybe they include an EPFCG... that would be really clever.
I wonder what that means, public + private key checks in the door?
http://www.ucsusa.org/nuclear-weapons/hair-trigger-alert/clo...
https://www.theguardian.com/world/2013/sep/20/usaf-atomic-bo...
It's such a complex network of systems and people and policies; all of which is constantly in flux. All of which has to yield a perfect result, every time. You can argue about robust systems, but the reality is that these systems are far from robust.
Look at what happened when the USSR collapsed for god's sake! We're still cleaning that up.