paragraph: Early in chapter 5 we introduced, along with Khalid Sheikh Mohammed, two other men who became operational coordinators for al Qaeda: Khallad and Nashiri. As we explained, both were involved during 1998 and 1999 in preparing to attack a ship off the coast of Yemen with a boatload of explosives. They had originally targeted a commercial vessel, specifically an oil tanker, but  Bin Laden urged them to look for a U.S.warship instead. In January 2000, their team had attempted to attack a warship in the port of Aden, but the attempt failed when the suicide boat sank. More than nine months later, on October 12,2000, al Qaeda operatives in a small boat laden with explosives attacked a U.S. Navy destroyer, the USS Cole. The blast ripped a hole in the side of the Cole, killing 17 members of the ship's crew and wounding at least 40. The plot, we now know, was a full-fledged al Qaeda operation, supervised directly by  Bin Laden. He chose the target and location of the attack, selected the suicide operatives, and provided the money needed to purchase explosives and equipment. Nashiri was the field commander and managed the operation in Yemen. Khallad helped in Yemen until he was arrested in a case of mistaken identity and freed with  Bin Laden's help, as we also mentioned earlier. Local al Qaeda coordinators included Jamal al Badawi and Fahd al Quso, who was supposed to film the attack from a nearby apartment. The two suicide operatives chosen were Hassan al Khamri and Ibrahim al Thawar, also known as Nibras. Nibras and Quso delivered money to Khallad in Bangkok during Khallad's January 2000 trip to Kuala Lumpur and Bangkok. In September 2000,  Bin Laden reportedly told Nashiri that he wanted to replace Khamri and Nibras. Nashiri was angry and disagreed, telling others he would go to Afghanistan and explain to  Bin Laden that the new operatives were already trained and ready to conduct the attack. Prior to departing, Nashiri gave Nibras and Khamri instructions to execute the attack on the next U.S.warship that entered the port of Aden. 
answer: In January 2000 operational coordinators for al Qaeda: Khallad and Nashiri had attempted to attack a warship in the port of Aden, but the attempt failed when the suicide boat sank