The strength of a country, and especially the strength of a city, is its ability to react to, and repair, the social fissures that originate wherever three or more humans live together. Social tectonics is the natural fracturing along societal lines like wealth, education, ethnicity, religion, sexual orientation, even color of skin, shapes of noses, or sports team preferences. Humans are amazingly adept at finding things in others to be wary of.
Social tectonics is active everywhere. No government or leader can stop it – but much can be done to reinforce our societies, institutions and cities, as well as reducing stresses. Like observant seismologists, social scientists sense where stresses are increasing and approaching breaking points. For example, the Occupy Movement that has popped up in many American cities represents growing stress in people who see too much concentration of wealth. The Arab Spring is a fracture between the general populace and the few who concentrated political power.