My first response was that the lefties (catchall phrase for purpose of this reply) I know fret over fairness. To even frame discussions in terms of power is seen as distasteful and largely avoided.

Then I was reminded that many lefties, especially younger cohorts, talk about privilege. In Ezra Klein's interview with Will Wilkinson, they discuss "white privilege" in terms of power. And power is a topic Ezra Klein is far more comfortable discussing (compared to me).

In conclusion, I mosdef agree that we lefties have a more systems-based view, where the relative power of the belligerents are considered. Further, the themes of privilege, equality, bias, opportunity, fairness (as used by misc lefties sub-cohorts) as rhetoric are really talking about relative power.