As astronauts look down on a bright blue-and-white ball, seeing our unique yet fragile home, they don't see, of course, a color map of the world's religions. With night and day passing every 88 minutes, they observe tranquil areas, typhoons, flooded areas, possibly occasional volcanoes – beauty and trouble that nature deals us, and about which we can do nothing.
The colors on a religious color map of the globe shows all of the Americas plus Russia as Christian (pale yellow) and, in green, most of north Africa and the Middle East plus Indonesia as Islamic.
If astronauts had orbited more than 2000 years ago the color map would have been different; gods popping up on mountain tops for the Greeks, elsewhere for the Hindus, and others such as Thor and Odin and Freyja for the Vikings.
Today's percentages for the nearly 7 billion world population are, in decreasing order of magnitude, approximately:
31% for Christianity (or ~2 billion)
23% for Islam (or 1.5 billion)
16% Unaffiliated – meaning agnosticism and/or atheism (or about 1 billion)
15% Hindu (i.e., another billion) –after which comes
Buddhism 7%, and Sikhism and Judaism at roughly 1% each
The commonality in today's map is that monotheism has replaced polytheism. But despite wide beliefs in just one god, the most common religions have all subdivided. Christianity has many sects and sub-divisions, that used to fight each other – for example Protestants vs Catholics in northern Ireland – and Islam has sects that still do fight each other, as we see with Sunnis killing Shiites, and vice versa.
The turmoil now – summer 2014 – stems from a fellow who, as has been common amongst Islamic leaders (think Libya's leader Khadaffi, or Iraq's Saddam Hussein) calls himself the new 'caliph' which is a title taken by successors to Mohammed, who lived in the 7th century. Just as professional genealogists have connected President Obama's pedigree to that of George Bush by going back fourteen generations, so it seems that almost any Middle Easterner might claim kinship to the Arabian prophet Mohammed by following the family pedigree back 1500 years. Be that as it may, this 'selfie caliph', going by the name al-Bhagdadi has formed a caliphate – a caliphate where all must follow the Sharia law he believes in, and death to those who dont.
Religious warfare is all such a waste of human life. Warfare for control – over oil, platinum or water, seems more understandable, and perhaps that sectarianism of faiths is only a cover.
Many religious beliefs get handed down, but I have never understood why succeeding generations tend to accept their parents' beliefs blindly, unwilling to think for themselves. Nor have I understood why so many people believe that in order to be a moral person you need to be affiliated.
Finally, Middle Eastern holy wars may never end, and some have suggested that the rest of the world should just let them fight it out, because blind faith cannot change. Guns and assassinations cannot make any kind of peace, of course, and just as gangs in big cities (a recent weekend in Chicago saw over 70 shootings, 14 fatal) could ultimately learn that cooperation would be an improvement, we may have to accept there's little we can do.
So the astronauts see a globe that we have to look after, and there are so many reasons for the earth's population to pull together.