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]
(..) No, not you. My master. - You mean me? - Well, yeah. - You picked up the bottle, didn't you? - All right, get out of the bottle. I command you. - You look ridiculous, - I feel ridiculous. Well, how am I supposed to get back to Greg now with this? Is that all you care about? (..)2004 TvShow: Charmed Title: I Dream of Phoebe Season: 6 Episode 15
(..) No, no, not Leo. Greg, the fireman. He's about to sleep with my mom. I really wish you wouldn't do that. - What just happened? - Your wish is my command, master. All right, where's the genie? Oh, my God, you landed one. She's a genie, not a trout. You still have two wishes, master. (..)2004 TvShow: Charmed Title: I Dream of Phoebe Season: 6 Episode 15