i'm going to start with kathleen hennessy of a.p. >> thanks, mr. president. i want to specifically ask about the dallas shooting and the attackers there -- attacker there now we know more about the man who did the crimes. i'm wondering if you could help us understand how you describe his motives. do you consider this an act of domestic terrorism? was this a hate crime? was this a mentally ill man with a gun? how should americans understand why that happened? and then also on the issue of political division and looking for solutions, there has been some critics that who noted that you immediately called about gun control. do you think that ensure that people treat their corners, let's say as they think about this? : first of all, i think it's very hard to untangle the motives of this shooter. in a whole range of incidents with mass shooters, they are, by definition, troubled. by definition, if you shoot people who post no threat to you, strangers, you have a troubled mind. what triggers that, what feeds it, what sets it off, i'll leave that to psychologists an