I think Simon Jenkins has it just right, tonight, for The Guardian -- do go read it all, but here is a bit:
. . .America's foreign policy is revealed as a slave to rightwing drift, terrified of a bomb exploding abroad or of a pro-Israeli congressman at home. If the cables tell of the progress to war over Iran or Pakistan or Gaza or Yemen, their revelation might help debate the inanity of policies which, as Patterson says, seem to be leading in just that direction. Perhaps we can now see how catastrophe unfolds when there is time to avert it, rather than having to await a Chilcot report after the event. If that is not in the public's interest, I fail to see what is.
Clearly, it is for governments, not journalists, to protect public secrets. Were there some overriding national jeopardy in revealing them, greater restraint might be in order. There is no such overriding jeopardy, except from the policies themselves as revealed. Where it is doing the right thing, a great power should be robust against embarrassment. . .