As some has already indicated, most of this is speculations. We don’t have time travel (yet) and the future is not fixed.
My very personal opinion is that there are three (alternate) things we can do get us all killed:
1) Pretend it’s just another day in paradise.
2) Give up, because we’ll never make it anyway.
3) Install global dictatorship implementing "THE TRUTH".
Forestman, it’s dangerous to live – one might die!
I think you’ve only scratched the surface of endless horrors... DISCOVER Magazine has an article on http://discovermagazine.com/2000/oct/featworld" that will keep you 'busy'...
1 Asteroid impact
2 Gamma-ray burst
3 Collapse of the vacuum
4 Rogue black holes
5 Giant solar flares
6 Reversal of Earth's magnetic field
7 Flood-basalt volcanism
8 Global epidemics
9 Global warming
10 Ecosystem collapse
11 Biotech disaster
12 Particle accelerator mishap
13 Nanotechnology disaster
14 Environmental toxins
15 Global war
16 Robots take over
17 Mass insanity
18 Alien invasion
19 Divine intervention
20 Someone wakes up and realizes it was all a dream
This was the October 2000 issue. To lighten up the mode somewhat

, Stephen Petranek shortened the list to 10:
https://www.youtube.com/watch?v=v9d65u3LfKs
Always remember 1: One day you could cross the street and be killed by a drunken driver!
Always remember 2: If we don’t do "anything" in approx 5 billion years, we’re smoked 100%!
EDIT:
AH! Nismars "Evil Overlord List" definitely puts period on the 'discussion'!
