She has a reputation that 'commands' attention/respect. [=people give her respect/attention because of her reputation]
In the United States, the President as the commander in chief is at the head of the military 'chain of command'.
She seems to be 'in (full) command of' the situation. [=she seems to have complete control of the situation]
(..) named King in the North and that murdering whore Sansa stands beside him. Enemies everywhere. We're surrounded by traitors. You're in command of the Lannister army now. - How do we proceed? - Winter is here. We can't win a war if we can't feed our men and our horses. (..)2017 TvShow: Game of Thrones Title: Dragonstone Season: 7 Episode 1