shrine to the prophet of americana

Basically when I hear something described as "galvanizing", or someone as "galvanized" I can never derive any metaphoric sense...

Basically when I hear something described as “galvanizing”, or someone as “galvanized” I can never derive any metaphoric sense in which they were coated to protect from rust. I can maybe get “an electric current running through them” from electroplating, is that supposed to be the concept?