$10,000. The FBI estimates it only cost about $10,000 to plan and execute the attack on the USS Cole that claimed the lives of 17 American sailors 17 years ago today.

The USS Cole was lingering in the Yemeni port of Aden, refueling, when terrorists affiliated with al Qaeda drove a small boat alongside the Navy Destroyer and blew themselves up. In addition to the 17 Navy service members who were killed and many more injured, the blast ripped a jagged hole in the side of the ship and threatened to sink it. The crew fought for days and managed to keep the ship afloat.

"Being surrounded by that... that death and that tragedy, was not a healthy thing," Operations Specialist 1st Class Greg Carlson told The Navy Times on the 15th anniversary of the attack. "It was hard thing. So when we were inside -- no light, no ventilation -- it turned that ship into an oven. All the perishable stuff starts to smell."

"I really want to think that was the majority of the odor was the food going over -- there was lots of food down there. But it wasn't just the smell of food," he said.

The FBI sent over 100 agents to investigate the attack, and representatives from the Naval Criminal Investigative Service (NCIS) and CIA went as well. Declassified documents show there were reports of at least six different militant groups claiming credit for the attack.

The 9/11 Commission would later report, "U.S. counterterrorism officials told us they immediately assumed that al Qaeda was responsible. But as [CIA] Deputy DCI John McLaughlin explained to us, it was not enough for the attack to smell, look, and taste like an al Qaeda operation. To make a case, the CIA needed not just a guess but a link to someone known to be an al Qaeda operative."

By November, they found their man. Yemeni law enforcement rounded up suspected associates of the attackers and eventually linked the attack to a man who a CIA/FBI source inside al Qaeda said was a "run boy" for bin Laden. Another known al Qaeda operative was also discovered to have been directly involved, the 9/11 Commission said.

A few months later, in March 2001, bin Laden appeared to put any doubt about al Qaeda's involvement to rest when a video reportedly appeared of him on the Middle Eastern news outlet al Jazeera reciting a poem which said in part, "In Aden, the young man stood up for holy war and destroyed a destroyer feared by the powerful."

Six months later, bin Laden sent four airplanes into targets in New York and Washington, D.C. That one was estimated to cost al Qaeda approximately $500,000.

READ MORE: Timeline of the USS Cole Attack, Investigation, Arrests (CNN)

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