Another note for benighted journalists who have, but too often do not honor, their duty to preserve and protect the English language in all her expressive and thought-guiding glory.
What one takes responsibility for may be either good or bad. What one takes credit for, however, is good. Terrorist acts are not good.
Therefore, do not report that ISIS 'took credit' for an atrocity but that they 'took responsibility' for it.
Walter (HT: Jeff Dunham) is the MavPhil 'icon' of the language rant. 'Icon,' however, needs it own rant. Later.