People 50 years ago probably didn't think the world would be able to sustain 7 Billion people today.
And they thought there would be a lot more people, but then they suddenly made birth control a lot easier
The black death would have killed us all, but we invented the quarantine.
Hydrocarbon gasse burn a hole in Ozon, but we eliminated the problem and the ozon layer is restoring slowly.
Carbon dioxide was going to warm up the earth, but CO
2 'sponges' are in development which are able to eliminate that problem too.
Oil is going to run out, but there already cars on hydrogen.
The natural condition of the earth is one of insurmountable obstacles on the road to imminent disaster...
... Strangely enough, it all turns out well.