Because the next time you watch a movie and someone yells "incoming rocket!" you can smile and think, "Actually, that’s a missile, buddy." It’s a tiny piece of knowledge that makes you feel smart. Plus, it’s just fascinating how a single propulsion concept—burning fuel to move—can branch into two completely different worlds: one of peaceful exploration, and one of precise destruction.
Rockets take us to the stars. Missiles protect (or threaten) the ground. Same muscle, totally different soul. Pretty cool, right?