Obama is sorry for drone-killing two Western victims. What about all the other innocents?

Surely not.
Interventionism is a nation’s activity which is proactive and non-defensive. Therefore, reactive responses cannot be considered interventionist.
Let me put this simply. If you are attacked and enter in to a war as a means of defense, that cannot be considered an interventionist action. If you attack a country without first being attacked then you can be said to have intervened in the course of another nation.