We are still in a cold war, only now it's more complicated because more countries have nukes...including North Korea which is kind of a wildcard.
Check out Nuclear War by Annie Jacobsen. It's a well-researched and horrifying scenario where deterrence fails because N Korea launches on the US. it takes you step-by-step through the decision process our government would take in response. Its gripping and pretty damn terrifying and shows just how delicate the whole situation is.
That looks good, got it added to my read list. Thx!