Editor's note: Peter Bergen is CNN's national security analyst, the author of "Manhunt: The Ten-Year Search for bin Laden -- From 9/11 to Abbottabad" and a director at the New America Foundation.
(CNN) -- George Venizelos, the FBI's assistant director in charge, asserted Thursday in a written statement that the recently arrested "Sulaiman Abu Ghaith held a key position in al Qaeda, comparable to a consigliere in a mob family."
This is overblown. Though he was Osama bin Laden's son-in-law, Abu Ghaith is far from a big fish in al Qaeda.
Bin Laden had quite a number of sons-in-law, having sired some two dozen children with five wives.
On Friday, Abu Ghaith pleaded not guilty in federal court in downtown Manhattan to charges of conspiracy to kill Americans. But the significance of Abu Ghaith's court appearance was not that he is a big player in al Qaeda. It's that the Obama administration has shipped him to New York for trial rather than sending him to Guantanamo to face a military commission, as has been the case with other members of bin Laden's inner circle.
Nothing in his past suggested Abu Ghaith was suited to play any operational role within al Qaeda. Before he joined al Qaeda a few months before 9/11, Abu Ghaith had been a high school teacher in his native Kuwait; he didn't have any experience fighting in other holy wars as most of al Qaeda's leaders had.
Abu Ghaith took on the role of spokesman of al Qaeda at the time of the 9/11 attacks, but that didn't mean that he had any operational role in them or even knew they were going to happen.
In a private al Qaeda videotape that was discovered by U.S. forces in Afghanistan after the fall of the Taliban, bin Laden is seen gesturing at Abu Ghaith and observing that his spokesman was not clued in on the 9/11 plans.
Abu Ghaith appeared in another videotape that al Qaeda publicly released a month after 9/11, sitting next to his father-in-law as bin Laden gloated about the success of the attacks.
Around the same time, Abu Ghaith also released a tape that publicly warned "Muslims in the United States and Britain ... not to travel by plane. We also advise them not to live in high-rise buildings and towers."
A year later, Abu Ghaith fulminated "Al Qaeda has the right to kill four million Americans, including one million children, displace double that figure, and injure and cripple hundreds and thousands."
But these are the words of a blowhard, not a man of action -- something that is underlined in the indictment against Abu Ghaith that was unsealed on Thursday. It charges him with conspiring to help al Qaeda by making speeches and persuading others to join the group but makes no allegations whatsoever of involvement in any actual terror plots.
After the fall of the Taliban in Afghanistan in the winter of 2001, Abu Ghaith, along with much more serious players in al Qaeda such as Saif al-Adel, the military commander of the group, fled from Afghanistan to Iran, where they remained under some form of house arrest for around a decade.
Abu Ghaith's decision to leave Iran to travel to Turkey led to the chain of events that resulted in him being taken in to custody by U.S. officials in the Middle East and then transferred to New York for trial there rather than incarceration at Guantanamo, Cuba.
This is a sound decision for several reasons:
First, the Obama administration's stated goal is to close Guantanamo, not to add prisoners there.
Second, the conviction rate since 9/11 in these kinds of terrorism cases is 100% in New York courts when it comes to allegations of any kind of involvement in al Qaeda or its allied organizations.
The New America Foundation maintains a database of all the jihadist terrorism cases in the U.S. since 9/11. Of the 39 cases in New York State since 9/11, 20 defendants pleaded guilty and 15 were convicted, while four await trial.
By contrast, the military commission system in Guantanamo is largely untested. The operational commander of 9/11, Khalid Sheikh Mohammed, was arrested in Pakistan a decade ago but still has yet to face trial in Guantanamo. It's quite possible that the process may take many more years before his trial even begins.
Indeed, of the 779 prisoners who have been held at Guantanamo, only six have been convicted according to a recently released study by the Congressional Research Service, which performs research on behalf of members of Congress.
In other words, while courts in New York have convicted alleged terrorists at a 100% rate, less than 1% have been successfully tried at Guantanamo.
In addition, the few convictions in Guantanamo have in some cases been overturned; for instance, that of Salim Hamden, who was bin Laden's driver.
In other cases, the sentences handed down have been very short compared with those in civilian trials of alleged terrorists in the U.S.
David Hicks, an Australian detainee at Guantanamo, plea bargained his way out of the camp with time served and nine months in an Australian prison.
Perhaps because of his relatively minor role in al Qaeda, the announcement that Abu Ghaith will face trial in Manhattan has not produced so far any of the "not in my backyard" response we saw when the Obama administration announced in late 2009 that it was planning to put Sheikh Mohammed on trial in Manhattan.
The political storm this unleashed forced the Obama administration to backtrack and to announce two years later that Sheik Mohammed instead would be tried by a military tribunal at Guantanamo.
If Abu Ghaith's case goes forward without a backlash in New York and a conviction is secured, as seems all but certain, we can be sure that he will not be the last alleged member of al Qaeda seized overseas who will be sent to the Southern District of New York to face trial -- rather than go before a military tribunal at Guantanamo Bay and all the uncertainties that such trials have hitherto encountered.
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