Train Whistle; Helicopter Blades, Vacuum Cleaner; Artillery Fire, Construction Noise; Grenade Blast, Fireworks; Bombs, Car Horns; Tank Treads, Airplane Flying Overhead; Bomb Dropping, Non-Palestinian; Palestinian. I still vividly remember my first day in Washington, D.C. I woke up in a panic, mistaking the sound of a police siren for an air raid.