In recent weeks, US officials have been falling over one another to denounce the brutality of the Bashar al-Assad regime in Syria. President Obama has accused it of committing "outrageous bloodshed" and called for Assad to stand down; Hillary Clinton has referred to the Syrian leader as a "tyrant"; Elliot Abrams, deputy national security adviser under George W Bush, has called Syria a "vicious enemy".

I can't help but wonder what Maher Arar must make of such comments. Arar, a telecommunications engineer born in Syria, moved to Canada as a teenager in 1987 and became a citizen in 1991.

On 26 September 2002, he was arrested at JFK airport in New York, where he had been in transit, on his way home to Canada after a family holiday abroad. Following 13 days of questioning, the US authorities, suspecting Arar of ties to al-Qaida based on flawed Canadian police intelligence, "rendered" him not to Canada, where he lived, but to his native Syria, from where his family had fled 15 years earlier.

For the next 10 months, he was detained without charge in a three-foot by six-foot Syrian prison cell where, according to the findings of an official Canadian commission of inquiry, he was tortured. Arar says he was punched, kicked and whipped with an electrical cable during 18-hour interrogation sessions. He received C$10.5m in compensation from the Canadian government and a formal apology from prime minister Stephen Harper for the country's role in his ordeal.

A decade on, the question remains: why did the US deport Arar to a "vicious enemy" country run by a "tyrant"? Was it because Canada couldn't use torture to interrogate Arar, so they decided to send him to Syria, which would? Human- rights groups have long believed the unstated aim of so-called "extraordinary rendition" was to subject terror suspects to aggressive methods of interrogation abroad that are illegal in America.

US officials cannot feign ignorance. They had every reason to believe the Syrians would abuse Arar. Six months earlier, in March 2002, the US state department's human rights report on Syria had concluded that "continuing serious abuses include the use of torture in detention". Arar claims his Syrian torturers were supplied with specific questions by the US government; he was asked the exact same questions in Damascus he had been asked in New York.

After his release, in October 2003, both Syria and Canada publicly cleared Arar of any links to terrorism. But the US government – first under Bush, and now under Obama – refuses to discuss the matter, let alone apologise. The Arar case wasn't a one-off. According to the New Yorker's Jane Mayer, who has spent much of the past decade investigating what she calls "the dark side" of the war on terror, Syria was one of the "most common" destinations for rendered suspects. Or, in the chilling words of former CIA agent Robert Baer, in 2004: "If you want a serious interrogation, you send a prisoner to Jordan. If you want them to be tortured, you send them to Syria."

Mohammed Haydar Zammar, a Syrian-born German citizen and alleged al-Qaida recruiter, was arrested in Morocco in October 2001 and rendered by the CIA to Syria, where he was held incommunicado in the notorious Far'Falastin detention centre. "US officials in Damascus submit written questions to the Syrians, who relay Zammar's answers back," reported Time magazine in July 2002. "State department officials like the arrangement because it insulates the US government from any torture the Syrians may be applying to Zammar."

The evidence is overwhelming: in the months and years after 9/11, the US collaborated closely with Syria, which became an ally in the war on terror and a frequent destination for victims of extraordinary rendition. Syrian torturers worked hand in hand with US interrogators.

These days, however, US politicians from across the spectrum piously condemn the Syrian regime for its crimes against humanity; two weeks ago, a bipartisan group of senators introduced a resolution condemning Assad for "gross human rights violations" and the use of "torture". Who says Americans don't do irony, eh?

And Arar? He's still on a US no-fly list. Some things, it seems, never change.

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