Well, duh, it's absolutely a matter of the power supply. Duh.
You impart kinetic energy to your reaction mass. For every action there is an equal and opposite reaction [whoa, dudes! The Philosophizer just had a huge metamental rush there!].
It's not like the air you're shoving down is pushing against other air - it's pushing against the underside of your propellor/impeller/ rotor/electrode! Think of the people in Newton's time, contemplating a rocket: "Push against your own ass? Preposterous!" But, yes, to move something, a force has to be applied to it, and that force has to come from somewhere, and that would usually (in the experience of every living being there's ever been since the beginning of time) be The Power Supply.
Dewd, gotta go have another hit... %-}
Cheers! Rich