Originally Posted by GuitarBizarre

Overpopulation leads to mass riots and geurrila warfare, the government are forced to take excessive action against their citizens and are turned upon, FIRE, THUNDER, EARTHQUAKES!

Leading to a massive use of force and a subjugation of rebel cells unless they agree to eke out a meager existence in government controlled enclaves. Total population devastation in the region of 80% and destruction of a huge amount of resources leading to hundreds of years of slow reclamation of destroyed land by a tiny workforce.