Sunday Roundup

This week the nation was horrified by yet another mass shooting -- this one in San Bernardino, as a heavily armed husband and wife killed 14 and injured 21 at a social services center. Within days, the F.B.I. announced that it was treating the carnage as a terrorist attack. While we may not be able to guarantee that such appalling events never happen, we can control our reaction to them. As investigators continue to look into the couple's motives, it's important that we not surrender our core values of tolerance and openness. The actions of a few have nothing to do with the nearly 3 million Muslims living peacefully in the U.S. Already, a mosque in Virginia has received death threats, and an Islamic center in Florida was vandalized. To give in to those impulses is to give the enemies of tolerance what they want. The actions of extremists and terrorists can't defeat us, but we can defeat ourselves.