In the long march of human civilization there has, in just the last few hundred years, developed a line of demarcation that will prove the success or failure of human societies in the future. It is not a line between rich and poor, liberal or conservative, north and south, Occident and Orient, or believer (of any faith) and infidel. Those divides are real but not existential. The existential difference is between people who would rather die or kill in the belief that they are more right than others, and people who are willing to admit the possibility that their own beliefs or self-interests are matched by those of others. It is the difference between people who look for what divides us, and those who look for what unites us.
Why am I thinking about this today? The 4th of July reminds us that 235 years ago a very small group of men (it would have happened more quickly if women were involved) subverted their deepest and most basic divisions to the strength of common interests. On that same date 150 years ago, thousands died on the fields of Gettysburg and thousands more surrendered the trenches of Vicksburg rather than find common ground. Today millions march in the streets of Egypt, struggling to grasp the ring of modernism, rationality, and democracy. Hundreds die in Syria, men kill aid workers in Pakistan, and single-minded political extremists in America fail to understand that lacking compromise, even on fundamental beliefs, our societies fail the test of sustainability.