[Defense Secretary Leon Panetta's] main mission was to pass on a warning from President Obama against any unilateral attack on Iran.Which would have more logically come from the State Department than the Pentagon. The presumably "leaked" claim that this was a warning is likely just cover for the Obama Administration in case an Israeli attack has, as is likely, disastrous consequences while Sec. Def. Pannetta passes along military advice -- especially about how Israeli planes can avoid awkward contacts with US air power on their way to the target areas.
Obama hopes to benefit from after the fact vocal support for a popular military move against Iran at no political risk to himself or military risk to US forces. It will be like Libya only better
Note: After the above was posted as a comment to the Washington Times article cited it was removed about a minute later. I have apparently made what the Washington Times takes to be a politically incorrect statement.