Mother with her little son was visiting an exhibition of Army weapons. The son got interested in seeing an antiaircraft missile system. He asked the sergeant in charge of presentation: "What's this?"
"An AA missile."
"What's used for?"
"To shoot down planes."
"Oh," cried out the youngster, "do let me see you shoot down that plane!" and he pointed at a plane flying not far away from the place.
Addressing the sergeant the mother said severely: "Now, don't you shoot down that plane for him until he says 'please'!"