dave cullen is here with us. he wrote the book "columbine" "new york times" best sell somewhere a portrait of the two killers there. dave, i'm curious, as to your thoughts as you learn about this latest tragedy mass casualty event. >> it's just horrifying. i mean obviously, i'm kind of numb in a way, my chest is really beating hard, which takes me back there. unfortunately i talk to a lot of the columbine victims and some of the other victims of tragedy and it brings them all right back there. some have actual flashbacks, most of them feel something in their body just like they're -- that day which is probably with them for life. >> and sadly, you know, it is how we have come to know places. >> yeah, it is. you know, i was hearing, listening, obviously, to people on the air. i have one bit of advice for parents there, if they're interested, from my experience. if you're a primary victim of survivor, most of the kids -- from columbine but a lot of the other tragedies that i've been following -- most of the kids des

i'll talk about it with dave cullen and dr.w pinsky. >> it's unnerving to hear this guy spell it out, killing leads to fame. we talked about it so many times and it's the reason we don't show the pictures of shooters and don't name them but i'm amazed so many other people do. >> i am, too. i was on your show that night talking about that. and it's just horrific. i was really glad to see president obama get angry yesterday and that night on that show, i came in angry and i decided, you know, normally i try to calm down and get -- but it's time we quit calming down and i get this all the time, they get more and more enraged. he's not going to name the names, which i think is really kind of -- there was a sheriff about a year ago that said that and he kind of went on a limb, none of the other sheriffs or police officers since then have taken that. finally a second guy is doing it and expanded a little to say his entire force, his investigation won't say it, i'm hoping this is a pattern now and others and maybe they can lead the me