The UN has repeatedly attempted to censure Israel for its agression and use of excessive force, and in most such cases the motions have been blocked by the United States. The UN is not apathetic, the UN is just being bullied by a member state which shouldn't have been given as much power as it has.
[rant]
That's like saying it's the (US) Democratic party's fault certain bills have or haven't been passed, when the Republican party can filibuster anything they put before the Senate, and when they have done so on more counts since they came into power than any other Senate in US history.
[/rant]