Just a guess, but I bet that during a recruits' military training the subject of torture comes up. Not a 8th/9th grade assembly.
Better they hear this before they ever make it to the recruiter's office no? What better place than a 9th Grade assembly? In three years many of those 9th graders would be eligible to go overseas and get a leg blown off for their country. Better they have a combat veteran up on a stage that gives them some food for thought before they ever make it to the recruiter's office.
I read Black Hawk Down. I went through basic training with one of the soldiers involved in that battle. One quote that struck me in that book involved a soldier thinking 'This is just like a movie'. Soldiers don't need to be sent out onto the battlefield thinking that Hollywood and actual combat are interchangeable.
Better children hear the truth even if it is unpleasant. And to tell you the truth, we didn't cover torture extensively when I went through basic training. We were given classes in the Code of Conduct and what was expected of us if we were captured. And I was an infantryman. Hopefully that's changed since then but as I said, one of the soldiers in the Mogadishu shoot-out was in my platoon in Basic.
I think the kid's question was honest and fair. Maybe tasteless, but not wrong particularly given that the military (and thus WAR) could be in his imminent future.