We are a rugged species, up for anything the universe can throw at us; and as the great gloominaries knew, we… — John Derbyshire

Unbelievers may think - all right, we do think - Christianity is only slightly less nutty than Islam; but Christianity is ours. We've got along with it for several centuries; and the relationship between Western unbelievers and Western Christians, if not always polite, is stable and comfortable. Can we fit Islam in like that?

All good ideas are of their time... and are liable to turn from blessings into blights if persisted in too long. The justifiable right of workers to organize in protection of their interests turned at last into featherbedding, the Teamster rackets, auto companies made uncompetitive by extravagant benefits agreements, and government-worker unions voting themselves ever-bigger shares of the public fisc. The campaign for full civil rights and racial justice turned into affirmative action, race quotas, grievance lawsuits, the Reverend Jeremiah Wright, and everlasting racial rancor.

After the many hundreds of generations that Australian, East Asian, African, European and indigenous American populations of Homo sapians developed in isolation from each other, in different environments, there ought to be divergence aplenty, though nowhere near to speciation. And so there is. That is why a roomful of Australian aborigines looks nothing like a roomful of Hungarians, and neither looks anything like a roomful of Quechua-speaking South American indigenes.