>> reporter: kelly caused a stir when he said his force is capable of taking down a plane about to attack. >> it really has to do with the concern about a plane, a slow-moving plane flying over new york city. it would be a very extreme situation, but we do have rifles that can be very high-powered rifles that can be fired from a helicopter. >> reporter: kelly also raised eyebrows by creating an elite intelligence and counter terrorism bureau, a first for a city in the u.s., even placing personnel overseas. some suggested he was overstepping his role. kelly disagrees. >> we want to add additional resources to help us better protect the city. if you look at the 9/11 report, obviously, there were failings with federal agencies communicating with each other. >> reporter: kelly rose to the top after starting as a lowly cadet, working on the switchboard before walking a beat. what was it about the job that really drew you to it?