Let's see, I know an atheist who is extremely homophobic. A few that are prone to resorting to violence. Excessive drunkenness, hard drug use that leads to violence, gang involvement, treating women like property, racism, and murders I have seen coming from atheist, agnostics, or were not motivated by religion. A couple years ago a girl was gunned down by a hit man. It wasn't because of a religious disagreement, but because one of her friends owed the wrong guy money for drugs, and she happened to be in the wrong place at the wrong time with the wrong crowd. And wars that have been fought for territory, resources, and political/rebellious coups are also the cons of religion without religion. We humans are a very violent species, and some of us are very territorial. We fight over possessions, mates, disagreements, and everything else including God. I used to work with a Marine who joined just to kill people and have a legitimate method of taking out his rage out on other people.
If you think about it, 9/11 wasn't caused by religion. In a nutshell it happened because of foreign policy and religion just happened to be the easiest way to convince people to carry out the attacks. Had they not been religious would we still have been attacked? Probably. Would it have been a suicidal mission? Doubtfully.