I should have posted this earlier in the week, but I've been really busy. I believe it ran last weekend in The Chronicle of Higher Education. The author of the article suggests that having enemies, and even creating new ones where none exist, is part of our human biology. Early humans evolved by fending off hostile animals, as well as hostile bands of fellow humans. We battled "others" to protect our tribesmen and resources, and we battled them to steal and secure new (their) resources. Today, we have a pronounced ability to make enemies. An almost genetic need to have one, even if only to swell our patriotic pride. (We'll get all those evildoers someday. U-S-A, U-S-A, U-S-A!) You need a subscription to read the article, but it's online here.
This was a really fun piece to work on. Thanks so much, Ellen!