When I attended police academy years ago, my instructors had a phrase for the quality that allows an officer to step in and take charge of a situation. They encouraged their students to develop this trait in how they deal with the public, suspects and victims in the line of duty. The term is "command presence."
Command presence can also be incorporated as a personality trait in an MC, a secondary character, even a villain, if you are selective in how you frame the words, actions and attitudes. Command presence should never be mistaken with hauntiness, superiority or conceit. It's an understated quality, more about how a character is perceived by other characters, not how he/she choses to view or interact with others. A character who demonstrates command presence instills confidence and trust in others. He/she is looked at as the natural leader, the one who calls the shots, the one who has the upper hand.
In P2PC, my male MC could not demonstrate command presence. He's a fish out of water, a fugitive, and at the mercy of the pilot who agrees to help him escape. It was a difficult chore for me to keep his character strong and someone the reader could respect under those circumstances; command presence was out of the question. (Though he does acquire clout as the story progresses, he is always a bold pawn, at best.)
Draxis is a another matter. My male MC is indisputably in charge and in his focal introduction in the story (though actually not his debut), I had to establish him as a force to be reckoned with in the eyes of the female MC. He has to be confident and capable to deal with his headstrong and often unpredictable match. At the same time, I had to avoid making him a "typical male MC hearthrob who has sexual power over woman and alpha male power over men" that I see in so many romances. I've edited his intro many times, because the trait of command presence is often understated and subtle. It took a few takes to get what I was going for, and not something that sounded like a starstruck gush.
Showing command presence in a character is about understatement and undercurrent. Chosing just the right words, thoughts, impressions to describe how he is viewed by others, how they react to him. The female MCs thoughts and perceptions of him were the key to the reader's impression.
Just because a character has command presence does not make him/her perfect, however. Command presence is more about knowing how to override flaws and weaknesses with "positive vibes." Having command presence is a lot like acting. No character can maintain command presence indefinitely. He/she is also human and eventually the warts are going to show. So command presence is akin to turning on a light bulb, and knowing when it should be on, and when it can be dark.
So how do you know if your 'command presence' traits are working in your character? That's where your critique partners come in. By analyzing their feedback on your character, you can get a good sense if he/she is oozing command presence or not, and if the scenes where it is demonstrated need more work. If you are hearing comments like "arrogant, assuming, presumptuous" then your character needs more work. If you're hearing words like "confident, powerful, take charge, leader" then you most likely have the command presence character trait down well.
Here are a few examples of well-known characters with command presence from cinema and television. Each of these characters are perceived as leaders or authority figures, though each demonstrates these attributes in different ways:
Glenda (Wizard of Oz)
Malcolm Reynolds (Firefly/Serenity)
Obi Wan Kenobi (Star Wars)
Jack Riley (The Hunt for Red October, Patriot Games, and other Tom Clancy novels)
Ellen Ripley (Alien, Aliens)
Captain Picard (Star Trek: TNG)
Captain Janeway (Star Trek: Voyager)