Terrorists and extremists may willingly sacifice themselves to delete any leader. China could mass-propogate that before you die you must delete an American. Every country must respond with war and nukes, or else sit and get deleted, but not before all the well-known leaders are deleted by brain-washed shock-troop kids and seniors. Leaders rising from the rubble are also deleted. Total anarchy ensues, no one working, mass starvation, no one working in hospitals or sewage, causing plague. If anyone survives the next 20 years of nuclear winter, plague, starvation, and deletion, those with a mindset more inclined to delete someone during their lifetime will go extinct. The peaceful will survive, with everyone becoming more and more peaceful as anyone who deletes may not reproduce.
Societies at first will work best in a Native American style, with many working in farms or hunting with their families, with everyone helping each other. With the peaceful gene, true, effective communism will be achieved.