Evolutionary psychologist Robert Wright sounded bleak in a couple of recent columns:

"Given the growing prospect that humankind, having reached the brink of a global community, will dissolve into chaos … you could say that our species is facing an epic moral test," he wrote at Meaningoflife.tv.

"In light of recent political and social developments in the United States and abroad," he wrote in The New York Times, "our work is cut out for us."

(Bangladeshi Islamists protest violence against Muslims in Myanmar.REUTERS/Mohammad Ponir Hossain)

Wright has argued in several books that expanding morality played a central role in human evolution, creating the framework for larger, more cohesive, and more powerful societies. Today, he says, mankind needs to take at least one more big step forward.

His 2010 book, "The Evolution of God," showed that we have at least come a long way already. In it, he described how religion had gradually moved toward respect for all people. For instance:

— As empires emerged in the ancient world, local religions began to take on universal characteristics, with moral codes that diverse groups could follow. Most notably, the tribes of Israel united in the belief in a one true god and the robust moral code embodied in the Ten Commandments.

— Christianity went a step beyond Judaism by offering salvation to anyone who converted.

— Islam could be seen as another step forward, as, at least occasionally, it claimed that people of various religions could find salvation. (Speaking on the difference between Jews, Christians, and Muslims, Muhammad himself said they "are but a part of the men whom He hath created! He will pardon whom He pleaseth, and chastise whom He pleaseth.")

Perhaps even more significant than the sequence of religions is how religions themselves have evolved. Islamic scriptures, for instance, contain both passages that are extremely antagonistic toward the rest of the world — e.g., "Kill the polytheists where ever you find them" — and others that are extremely tolerant — e.g., "To you be your religion; to me my religion."

Wright argues that the driving factor in these changes is the perception of non-zero-sum relations: In situations in which both sides can benefit, people find a way to get along. Since human civilization is, in the long run, a non-zero-sum game — that is, we all gain when we work together and lose when we fight — moral and religious systems have tended to move toward greater harmony.

(A Muslim woman reads the Quran in Indonesia.Tatan Syuflana/AP)

This brings us to today, when radical Muslims are fighting a terrorist war against the West, and radical Westerners are looking to fight fire with fire.