While the former seeks to cripple Iran's nuclear program, the latter has been in a deadly confrontation with the Islamicly-oriented government for decades, and wants to weaken the regime so it could be toppled. Both entities have tried over the years to sponsor terrorist operations and covert actions both within and outside Iran in order to damage the regime or implicate it in external terrorist acts.
It is not beyond the realm of possibilities that the Israeli Mossad or the MKO were able to recruit an idiot or his cousin -- or both -- in a plot that involved assassinating the Saudi Ambassador, while leaving a trove of evidence behind to be found in order to implicate the Iranian government.
But assuming the U.S. was not privy to it, despite the plot being a sting operation, the more important question is then why the U.S. government took the bait and escalated the incident to a dangerous course with uncalculated consequences?
The U.S, Israel, and Saudi Arabia can certainly start a war with a more assertive Iran. But they certainly cannot end it. One only has to look at the recent U.S. adventures on either side of Iran's borders to learn that lesson.
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