from the tisch wnet studios in lincoln center in new york, john larson. >> larson: good evening, and thanks for joining us. i'm john larson in for hari sreenivasan. french officials have confirmed the identity of the would-be mass shooter who terrorized a passenger train in europe on friday night and say he is an "islamic extremist." the officials say ayoub el- khazzani is a 26-year-old from morocco who lived in spain until last year, and reuters reports he traveled to war-torn syria. el-kazzani was convicted of drug dealing in spain. tonight, he remains in french police custody. french officials say el- khazzani, armed with an ak-47 and a luger pistol, boarded an amsterdam-to-paris train in brussels with a backpack full of ammunition. an attorney assigned to represent the gunman-- seen here after he was subdued and tied up by passengers-- said he merely intended to rob passengers, not kill them and that he does not belong to any terrorist group. >> ( translated ): asked him about his motivations, if he had received instructions, if there was a sponsor. these are the first questions

from the tisch wnet studios in lincoln center in new york, john larson. >> larson: good evening. thanks for joining us. i'm john larson in for hari sreenivasan. the presidents of france and of the united states are praising three americans who subdued a gunman who attempted to carry out a mass shooting on a passenger train heading toward paris. the high speed thalys train, going from amsterdam to paris last night, had 554 passengers on board. among them were three american friends in their early 20s: spencer stone, anthony sadler, and alek skarlatos, two of them active members of the u.s. military. the gunman boarded the train in brussels. he entered a passenger car carrying an ak-47 assault rifle, an automatic handgun, and a box cutter. stone, who is in the air force, ran down the aisle and tackled the gunman. >> i think spencer is the real hero. he was the first one to jump on him. he is the one who got cut up. like, none of us are injured but spencer. spencer took a few injuries, and he just had no fear. and he's our friend, so once we saw him go, we had to go join him, like w

we continue the conversation, brett larson and john broad with me there.have a quick break and we will be back with more on "risk & reward." ♪ fresher dentures with polident. for the best first impression. love loud. live loud. polident. number 1 dentist recommended. . deirdre: as we have been covering google's reorganization will potentially give it freedom to invest in the moon shot projects. devin is with me now, as a tech investor, does this change anything that you do at insight? >> i don't think it changes anything we do at insight. we only invest in private companies. it was a smart strategy by google, there's lots of ways to provide transparency including simply doing segment reporting. what it does do is allow them the flexible to the create independent entities and recruit a-class talent who want their own ceo jobs. deirdre: all right, i want to folks on your news at insight, have you closed a $5 billion fund. what does this say about demand, especially for software and cloud software companys? >> look, i think the demand for software remains una

i was able to follow john green on the stage and that was difficult and today it is eric larson. i don't know if that is a compliment or a highly placed second violin but i am happy to be here. i tweeted out the other day, yes, i tweet, the notion that you know, let's play, too. eric larson and me, back-to-back, a history doubleheader. let's go for it. >> host: ken, i am going to launch into the themes of your new book and one i thought just to explain how the book is constructed and correct me i get anything wrong. >> guest: oh, i will. >> host: it is from six different wars focused on a single battle or city or struggle. and the interesting about the book is certain themes all the way through. one is who fights the americas war. the militia versus the army and in the iraq time there were more military contractors in iraq than uniformed personal which is an amazing thing to think about. can you talk about who fights america's wars and why that matters. >> guest: absolutely. let me first explain many people do know me from the don't know much about series and history that was pub

here a few years ago and had the good fortune to follow john green onto the stage, and that was a challenge in itself. today i follow erik larson onto the stage -- [laughter] i don't know if that's a compliment of just a very, very highly placed second violin. but i'm happy to be here, thank you very much. [applause] i actually, since we just heard the word "twitter," i actually tweeted out the other day -- yes, i tweet -- the notion that, you know, let's play two. i think a famous chicagoan said that, erik larson and me back to back, a great history doubleheader. let's go for it. >> some of the themes of your book, and one of them i thought was, and just to explain how the book is constructed, and correct me if i get any of this wrong -- >> oh, i will. >> it's six essays, the really interesting thing about book is how there are certain themes that go all the way through. one of them is who fights america's wars, and you talk about how in the american revolution the militia versus the actual members of the continental army and all the way to the iraq war, you get into how at one point in time there were more military contractor