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]
(..) The Elf-maiden who gave her love to Beren,a mortal. What happened to her? She died. Get some sleep,Frodo. The power of Isengard is at your command... ... Sauron,Lord of the Earth. Build me an army worthy of Mordor. What orders from Mordor,my lord? What does the Eye command? We have work to do. (..)2001 The Lord of the Rings: The Fellowship of the Ring