After reading this I feel like the SF catastrophe movies are not far from fiction
That has always been the beauty and horror of sci-fi. Some of it is pure fantasy, but the really good stuff is rooted in science and the extrapolation thereof.
While I like Space Opera, my favorite authors have always been the "hard" writers like Robert Anson Heinlein, Isaac Asimov, Ben Bova, G. Harry Stein, C.M. Kornbluth, and others of that ilk.
Growing up in the seventies and eighties, I (and a great many of my generation) expected the world to end in a nuclear fireball long ago. By some miracle, it hasn't happened.
That being said, the actions taken by the sons of bitches who rule my nation are doing their damnedest to make it happen. Our only saving grace is that their power greed is matched in at least equal part by their stupidity. About the only good thing about a democratic republic is that the elected are mostly idiots. Powerful idiots, but idiots nonetheless.
What I fear above all is that at some point a SMART politician who is mad as a hatter gets the nuclear control codes. The modern Pol is a power hungry sob, but not too bright. They don't seem to understand that deliberately sowing hatred and provocation of every potential enemy has drastic and long lasting consequences. One who did, and could unite enough of the haters, would be the most dangerous thing that earth could face.
This, aside from all my romantic notions, is why I think that we, as a species, need to develop starships. Our survival as a race, Imao, depends on us getting a viable population far enough offworld that one madman with access to nuclear weapons can't pull the plug on us.
The technology is in our grasp. We've had the technical ability to build starships since I was born, other than the necessary computer power for long range navigation. That now exists on most everyone's desktop. At this point, all we lack is the will to do it. Nations are not going to, as it's not in their interest to have free colonies offworld. They might get notions of independence, after all.
But the corporations, whatever you think of them, do have the power if they had the will. I suspect that men such as Sir Richard Branson might have the will, and they certainly have the power.
My father's generation was the first to see a time when humanity had the power to destroy itself, and most life on the planet. That is the legacy we have, and which we must undo. Obviously, we can't put the genie back in the bottle. But we can go forward and find a way to live where these terrible weapons are no longer a threat to absolutely everything.
There is a term in sci-fi and some philosophy that applies. The Nuclear Decision Threshold. The point at which a species that has developed nuclear weapons finds a way past their awful power, or perishes. We have been on that threshold for 63 years. Not a long time, but the threat looms large. And while it is not on everyone's minds and lips as it was just two decades ago, the threat has not diminished. If anything, it has increased because America thinks they can win a nuclear exchange, and there are several new players.
Conventional wars are horrible, but they are nothing compared to a full scale nuclear exchange. Because of the time frames involved, the idea of a limited nuclear exchange is pure madness. If one country launches, the others will too. They have no choice as the system sits. "riding it out" is simply not an option. It's launch on detection, or lose. But there are no possible winners, so it's lose period. Mutually Assured Destruction. When the USSR and the USA were playing their games of brinkmanship, that was always on the minds of the leaders and the proles. Now, it's not so much, especially in the public eye. That, in my opinion, is a more dangerous state of affairs than the two "superpowers" eyeballing each other over gunsights.
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I think it's a good start. By starships,I don't mean FTL, though I don't believe it impossible. Something that would push at about .9 C would get us to the nearest stars, even though "on ship" culture would probably vary radically from the land bound due to time dilation. 
