Viktor Bout's sentence was the mandatory minimum he faced, though federal sentencing guidelines had called for life in prison.
U.S. District Judge Shira Scheindlin in Manhattan said it was sufficient and appropriate because Bout's crimes originated only because of an elaborate sting operation created by the Drug Enforcement Administration to catch one of the world's most notorious arms dealers.
She said there was no evidence the 45-year-old Bout, a vegetarian and classical music fan who speaks six languages, had ever planned to harm Americans or commit a crime punishable in U.S. courts until the sting was created.
"But for the approach made through this determined sting operation, there is no reason to believe Bout would ever have committed the charged crimes," she said.
As Bout left court, he hugged his lawyer and waved to his wife.
Minutes earlier, he had appeared angry when he interrupted a prosecutor who said he agreed to sell weapons to kill Americans, shouting in English: "It's a lie!"
Earlier, speaking through a Russian interpreter, he told the judge he "never intended to kill anyone" and said, "God knows this truth."
The sentencing came four years after Bout's arrest in Thailand, where he was held before his extradition to the U.S. for trial in late 2010, and months after a jury convicted him of four conspiracy charges relating to his support of a Colombian terrorist organization.
The judge also ordered a $15 million forfeiture.
The government had portrayed Bout, the inspiration for an arms dealer character played by Nicolas Cage in the 2005 film "Lord of War," as one of the world's worst villains, capable of empowering dictators in war-torn countries by supplying weapons that they could turn on their own people. The defense had countered that Bout was a political prisoner, a victim of a sting operation that made it seem as if he hated Americans and was willing to sell surface-to-air missiles to a Colombian organization to shoot down American helicopters.
Assistant U.S. Attorney Brendan McGuire urged the judge to send a message with a life sentence to others like Bout, saying 25 years would be "insufficient" because general deterrence was critical in the case.
Defense attorney Albert Dayan told the judge: "He's no terrorist." He had asked that the jury verdict be reversed and that the charges dismissed.
Bout told the judge he was "not guilty" and said allegations against him were false.
But prosecutors said Bout's weapons fueled armed conflicts in some of the world's most treacherous hot spots, including Rwanda, Angola and the Congo and that he was looking for new arms deals in places such as Libya and Tanzania when he was arrested. Bout has maintained he was a legitimate businessman who wasn't selling arms when the American operatives came knocking.
Federal prosecutors said the government initiated its investigation in 2007 because Bout "constituted a threat to the United States and to the international community based on his reported history of arming some of the world's most violent and destabilizing dictators and regimes."
"Although Bout has often described himself as nothing more than a businessman, he was a businessman of the most dangerous order," prosecutors said in their pre-sentencing memo. "Transnational criminals like Bout who are ready, willing and able to arm terrorists transform their customers from intolerant ideologues into lethal criminals who pose the gravest risk to civilized societies."
Dayan wrote in a defense submission to the judge that the United States targeted his client vindictively because it was embarrassed that his companies helped deliver goods to American military contractors involved in the Iraq War.
The deliveries occurred despite United Nations sanctions imposed against Bout since 2001 because of his reputation as a notorious illegal arms dealer, Dayan said.
The lawyer noted that the U.S. Department of the Treasury imposed its own ban on dealings with Bout in July 2004, citing in part the "unproven allegation" that Bout made $50 million in profits from arms transfers to the Taliban when Osama bin Laden and al-Qaida were based in Afghanistan.
The Merchant of Death moniker was attached to Bout by a high-ranking minister at Britain's Foreign Office, who had drawn attention to his 1990s notoriety for running a fleet of aging Soviet-era cargo planes to conflict-ridden hotspots in Africa.
The nickname was included in the U.S. government's indictment of Bout, and U.S. Attorney Preet Bharara referenced it when he announced Bout's extradition in late 2010, saying: "The so-called Merchant of Death is now a federal inmate."
After the sentencing, Bharara in a statement called the sentence "a fitting coda for this career arms trafficker of the most dangerous order."
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