Oh man, now my head-Iroh's thinking that too. He's lost another son to Ba Sing Se.

To make me feel better, my personal headcanon for this has Katara fixing him after sitting down to tea and getting the scare of her... day? She goes through some hair-raising stuff, bit I digress.

At least in Zuko's case "The Earth King has invited you to Lake Laogai" means "go serve tea" instead of "go attack the avatar's friends."