If I walked into the room to teach my youth karate class, found a mess, and asked my students, "Who is responsible for this?", they would probably think I was trying to find out who to blame. Whose fault was it that this had occurred? We often think of words like "blame" when the word "responsibility" comes up.
But there's another sense of the word which is right there in the pronunciation, if not in the English spelling: "response-able". Indeed the word comes to us French "responsable", and the 1913 Websters gives one definition as "Able to respond or answer for one's conduct". We can trace it back to the Latin "spondeō" meaning "I promise, bind or pledge myself."