>>63871698
P Reeve's Mortal Engines series has the world destroyed by directed asteroids - when each country is nuked by it's neighbour, they also activate pre-prepared directed asteroids that arrive randomly over the next few years/decades as revenge weapons, pummeling the planet even further. causing earthquakes, new continental plate faults, volcanoes, tidal waves, etc worldwide. Nothing could be done about them as most nations are fucked up after multiple nuclear strikes and any space forces wiped each other out in the first few days. They called them 'Slow Bombs'.