Is it possible that you have had a conversation that made a huge impact - and you didn't even know? Maybe you always treat people that way. . . but on a particular day with a particular person, the way you always treat people made a difference. Maybe you were just doing your job - but on that day, for that person, doing your job meant something important. Maybe you were just having a great day, and your smile made someone else dream a little. . .
People will often tell you that power happens intentionally. This is only partly true. Some power is intentional, and all power involves elements of engagement and intention. Often, being intentional both opens up the possibility of power and underscores the actions we take. Your intention does make a difference.
Other things make a difference, too. Good results can sneak up on you. This is more likely if you practice having a good relationship with you. Yes, it's nice to be good at rapport but the primary benefit of rapport is that you learn something - rapport gives you new information. The more you practice being open to information and respectful of the impact it has on you, the more you are likely to put information into the world that makes a difference.
Don't believe me? That's probably because you're thinking about yourself. When you consider conversations where you have received power - a difference that came from words or ideas or connection - you'll find you were often talking to someone who seemed to you to "have it together." The people that make a difference often seem less interested in having power over us and more interested in accurate observation of the way their internal experience is interwoven with their place in the world.
Have you ever engaged in a conversation with someone who is wide awake and grounded and not felt that power was possible?