I think it's from the Voyager episode 'Night' (but I may be wrong) where Paris attempts to involve Seven in his Captain Proton program...
Robot: Citizen of Earth...Surrender, do not resist!
Seven of Nine: I am Borg. (Dismantles and deactivates the robot in two seconds).
The robot has been neutralised, may I leave now?
From 'In The Flesh'...
Doctor: Optimism Seven! Try to look on the bright side.
Seven of Nine: In Earth's Third World War, nuclear weapons accounted for 600
million casualties. Were they looking on 'the bright side'?
Robot: Citizen of Earth...Surrender, do not resist!
Seven of Nine: I am Borg. (Dismantles and deactivates the robot in two seconds).
The robot has been neutralised, may I leave now?
From 'In The Flesh'...
Doctor: Optimism Seven! Try to look on the bright side.
Seven of Nine: In Earth's Third World War, nuclear weapons accounted for 600
million casualties. Were they looking on 'the bright side'?