A Double standard? Vive la petite difference...

[U.S. Defense Secretary Robert Gates] dismissed the allegation that the United States applied a double standard on the nuclear issue by supporting Israel while calling for Iran to abandon its enrichment activities, which Tehran says are for peaceful purposes.

He listed the differences:

Israel is not training terrorists to subvert its neighbours.

It has not shipped weapons into a place like Iraq to kill thousands of innocent civilians covertly,"

It has not threatened to destroy any of its neighbours.

It is not trying to destabilise the government of Lebanon.

Concluding with:

So I think there are significant differences in terms of both the history and the behaviour of the Iranian and Israeli governments.