This 1996 image provided by the Nueces County Sheriff's Office...

This 1996 image provided by the Nueces County Sheriff's Office shows Manssor Arbabsiar, who was indicted on multiple conspiracy counts for allegedly trying to recruit a Mexican drug cartel to kill the Saudi Arabian ambassador to the United States. Credit: AP

The hapless Texas used-car salesman who was at the center of a bizarre Iranian plot to assassinate the Saudi Arabian ambassador by bombing a Washington restaurant was sentenced to a maximum 25-year prison term in federal court in Manhattan Thursday.

U.S. District Judge John Keenan told Manssor Arbabsiar, 58, an Iranian-American who claimed his judgment was impaired by bipolar disorder, that he just didn't buy the claim that the entire plot was a six-month-long "hypomanic" episode.

"In a case like this, deterrence is of supreme importance," Keenan said. "Others who might have financial or political purposes in engaging in acts of violence against the U.S. or its interests must learn the lesson that such conduct will not be tolerated."

Arbabsiar, a naturalized American with dual citizenship, pleaded guilty last year to attempting to hire a Mexican drug cartel for $1.5 million to carry out the hit on Saudi Ambassador Adel el-Jubeir at the behest of a relative and others who were part of the Iranian Revolutionary Guard Corps Qods Force.

He received a $100,000 down payment from Iran and transferred it to his drug cartel contact -- who was actually an FBI informant. When the informant noted that killing the ambassador in a popular D.C. restaurant would cause mass casualties, Arbabsiar said it was "no big deal."

Arbabsiar's lawyer urged a sentence of 10 years, telling the judge that while her client had never been very successful at a series of jobs and businesses, he had been good to his family, worked hard and never had a brush with the law until his involvement in the plot.

"I take responsibility for it," Arbabsiar said in his statement. "I can't change what I did. I have a good heart. I never hurt anyone. My mind sometimes is not in a good place. It runs faster than myself."

After he was caught, Arbabsiar made calls to the men controlling him in Iran to help the FBI gather evidence. But he decided to stop cooperating, and as a result, Keenan said, he didn't deserve any break for the assistance he did provide.

Arbabsiar pleaded guilty to murder for hire, conspiracy to commit murder for hire, and conspiracy to commit an act of terrorism transcending national boundaries. Charges are still outstanding against one of his Iranian superiors, a Qods Force senior official named Ali Gholam Shakuri, who is at large.

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