To be fair, Luke was no longer officially affiliated with the Rebellion. But why didn't Leia get a promotion? In fact, why was she not ranked at all? Was it her diplomatic status? Does the EU address the non-military nature of her rebel participation?

She certainly sacrified a lot during the Jabba mission to rescue Solo. There's a pretty big gap between her capture and her stoic, subdued appearance at Jabba's side in the slave gear that we in the audience know nothing about. Something must have happened between the giant slug and Slave Leia offscreen.

(And by "giant slug" I may or may not mean (all of) Jabba the Hut.)

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