One of the most considerable disaster ( war ) is. Skam is said that caused the collapse of society and Helas is said that suffered a partial nuclear war. Artificial planets like Skam are supposed to suffer this disaster mostly. It is standard disaster for THEM.
In our planet, I found Alii Type Lady tried to entice North Korea to use atomic bombs in several times. She did not mind that North Korea did not have such powers. It would be THEIR standard matter. It is often seen for THEM that THEY does not take care of the situation around this world. THEY did often take automatic thoughtless actions like this.
In other planets, it is seemed hard for THEM to make nuclear war. International opinion will stop doing such a thing. However it is, THEY would try to make nuclear war. THEY have decided it carried out for the level of depravity. Nothing to tell, THEY had depraved native people at all.
By the way, Black-Hole-Bomb War would occur never. It is aweful enough that no one would consider to use ( but Rei people supposed to use it. We can see this stupid man even for now ). This bomb can destroy a whole planet by one shot.
It might be safe to develop our technology on this level.
May The Earth in peace.