At the outset of World War II, the German Luftwaffe attached an ear-splitting siren – the Jericho Trumpet – to the Junker Ju-87 dive-bomber, commonly called the Stuka. Dive-bombers are wonderful tactical aircraft if you have control of the skies, highly effective against tanks, vehicles of all sorts, even smaller ships, but they simply don’t carry enough ordnance to be a strategic weapon. They can certainly help you win a battle, but they’re unlikely to help you win a war. By attaching the Jericho Trumpet, however, the Stuka became a psychological weapon as much as a physical weapon, striking fear in a much wider swath than the actual bombs. During the early Blitzkrieg days of the war, the Stuka had exactly this sort of strategic effect, crushing the morale of the Polish army in particular.