You know, when something says that we are so close to destruction for over half a century... well you have to wonder why anyone would put any stock in it. It is a bit hard to reconcile with being on the edge of destruction, and yet everything continuing to not be destroyed.
Did you know the most dangerous drivers are not those who have just gotten their license, but those who have had a bit of experience? The reason is that new drivers are all too aware that they're one bad decision away from being gruesomely killed, while those who have driven for a while let their guard down because "nothing's happened so far, so nothing ever will".
This is true for dangerous acitvities in general. Someone who's handling boiling acid for the first time will make damn sure to think what they're doing. Someone who's done it a hundred times is busy thinking what they'll be having for lunch. And then acid gets somewhere it shouldn't, and suddenly things get very exciting again.
We haven't been destroyed because we've been very lucky. During Cuban missile crisis American ships actually dropped depth charges on a nuke-carrying Russian submarine. The captain and the political officer were all for launching it in retaliation, but the idea was vetoed by Vasili Arkhipov. And it's not the only time humanity's fate has hung on the decisions of a single person.
And of course this is all ignoring the possibilities of, say, biological warfare advancing technology is bringing to within reach of even non-state actors. You may not have noticed, but some of these actors are nowhere near as rational nor benevolent as the Soviet Russia of old.
Finally, the dawning of the Information Age is challenging whole new facets of human capacity for evil. Hypocrisy is quickly becoming impossible as privacy continues to erode. At the same time, anonymity serves to strip away pretensions of civility and expose the grinning skull beneath all too many faces. With Industrial Age, the choice was "cease warring or die"; with Information Age it's "stop being hypocrites or have your souls crushed". Given that it took two world wars to get humanity to the point where we had any chance to survive harnessing the power of the atom, I shudder to think what it'll take to prepare us for omnipresent computation.
We're running a gauntlet, a purgatory forcing us to choose between our shadow or increasing amounts of pain. Every aspect of our existence is being confronted by its shortcomings like never before, for there are no more second chances. Humanity will either demonstrate it has mastered its dark side before it will master nature and reach the stars, or it will send itself to oblivion so more worthy beings might inherit them instead. It's not two minutes to midnight, it's Judgement Day.