Where is the "dominant market power" coming from?

Asymmetry of information is what got you to the top. You know more than your competition, more on a productive process, on consumer behavior, on business partners, on leveraging financial avenues, on political "contributions", on questionable use of insider information, etc.

And Information is what keeps you at the top: knowing who to "lobby" to create convenient regulation that hurts your competition the most, is the most effective way monopolies use to stay that way.

Monopolies are not monopolies in the abstract, they have to fight everyday to keep being a monopoly and they do that by leveraging information asymmetry.