Just as we're starting to have a national discussion on drone warfare, and the legal and ethical issues of killing suspected terrorists (and sometimes bystanders) using remote-controlled aircraft, the Obama administration threw a curveball. Sulaiman Abu Ghaith, a high-level al Qaeda adviser and spokesman — and a son-in-law of Osama bin Laden — was reportedly arrested in Turkey a few weeks ago, nabbed by the CIA in Jordan as he was being deported to his native Kuwait, and spirited to New York City, where he will appear in court today.

On Thursday, federal prosecutors unsealed an indictment against Abu Ghaith detailing terrorism-related charges, including conspiring to kill Americans, that could earn him a life sentence. An influential Muslim preacher in Kuwait, Abu Ghaith moved to Afghanistan in 2000, met bin Laden, married his daughter Fatima, and, according to the indictment, urged Muslims in Afghanistan to swear allegiance to bin Laden. Abu Ghaith also agreed to help bin Laden, when asked, on the night of the Sept. 11, 2001, attacks. Since 2002, he has reportedly been living in Iran.

He is most famous, however, for being "at the forefront as al Qaeda agents threw salt in the wounds of a reeling, post-9/11 America," says John Hudson at Foreign Policy. As the Justice Department put it Thursday, Abu Ghaith held a "key position in al Qaeda, comparable to the consigliere in a mob family or propaganda minister in a totalitarian regime." In early October 2001, he appeared in several videos promising "that the storm of plane attacks will not abate" and "the battle will continue to be waged on [America's] territory until it leaves our land, stops its support for the Jews, and lifts the unjust embargo on the Iraqi people." In 2002, he said that al Qaeda had the "right to kill 4 million Americans, including 1 million children, displace double that figure, and injure and cripple hundreds and thousands."

His capture, intelligence officials and experts tell us, is a big deal. "This is not a small fish," National Defense University's Thomas Lynch tells ABC News. His capture and prosecution will send "a message in two directions":

First, even these guys who have [hidden] successfully for a while are not safe from identification and capture. The notion of impunity is further tarnished. Second, Abu Ghaith is one of 10 guys left from al Qaeda core that have the financial ties and reputation who might have been able to get the old band back together to execute spectacular international terror attacks. [ABC News]

Naturally, Obama's decision to try him in federal courts, and especially in lower Manhattan, has reopened the still-festering disagreements in Washington about how to treat foreign terrorism suspects, most famously illustrated by the Obama administration's thwarted decision to try Khalid Sheikh Mohammed (KSM) in the same courtroom. Republicans, and some Democrats, want all terrorism suspects to be held at Guantanamo Bay and tried in the ad hoc military tribunals set up there. They wasted no time pointing that out.

"Al Qaeda leaders captured on the battlefield should not be brought to the United States to stand trial," Rep. Mike Rogers (R-Mich.) told MSNBC. "We should treat enemy combatants like the enemy." Abu Ghaith "should be in Guantanamo Bay," said Sen. Kelly Ayotte (R-N.H.) in a news conference with Sen. Lindsey Graham (R-S.C.). "When we find somebody like this, this close to bin Laden and the senior al Qaeda leadership, the last thing in the world we want to do, in my opinion, is put them in civilian court." Graham added that he's "putting the administration on notice.... We think that sneaking this guy into the country, clearly going around the intent of Congress when it comes to enemy combatants, will be challenged."

The main objection to trying terrorists in federal courts is that they will be given the right to remain silent. Abu Ghaith "surely has been Mirandized and soon will have a procedurally savvy lawyer advising him to say as little as necessary," says The Wall Street Journal in an editorial. "Experienced federal attorneys may indeed convict. Good. But we remain concerned that the civilian route is likely to produce less useful intelligence than the Guantanamo-based system, and that is not good."

But the Obama team learned some valuable lessons from the KSM debacle. The first one: Get New York lawmakers on board. Rep. Peter King (R-N.Y.), who was first to leak the news, commended "our CIA and FBI, our allies in Jordan, and President Obama for their capture of... Abu Ghaith," adding, "I trust he received a vigorous interrogation, and will face swift and certain justice." Sen. Charles Schumer (D-N.Y), another critic of trying KSM in New York, also gave a thumbs-up. "Unlike with KSM, (police Commissioner Ray) Kelly and others had been consulted ahead of time about this, and they gave the green light to do it," he said. "On issues like this, I defer to Commissioner Kelly, and I think the mayor does as well. And he thinks it's OK to do it here, and I'll go by that."

Second, Obama crossed his t's and dotted his i's, says Massimo Calabresi at TIME. Graham and Ayotte have a point: "By law, Abu Ghaith should have been transferred to military detention under the provisions of the Fiscal Year 2012 National Defense Authorization Act, which requires all members of al Qaeda or associated forces to be taken into military custody at least temporarily." But Obama utilized the "wide carve out" included in the law, exercising a waiver that allows him to disregard the provision if he believes it is in America's national security interests. The president may not have told Graham his plans, but he did inform congressional leaders, administration officials say.

Finally, Obama used a version of the old saying about how it's easier to ask forgiveness than permission. While the administration informed Congress of its intent to transfer KSM to New York from Guantanamo, "in the case of Abu Ghaith, the administration seems to have avoided the political trap by presenting Congress with a fait accompli," says TIME's Calabresi. By the time the public learned we had captured Osama bin Laden's son-in-law, he was already waiting in a jail cell a few blocks from the construction of the new World Trade Center complex.