The USS Cole suffered a surprise attack by al Qaeda suicide bombers while at port in Yemen — killing 17 American sailors and wounding about three dozen others, on this day in history, Oct. 12, 2000. 

It proved an ill-heeded harbinger of much more terrifying al-Qaeda attacks on the United States' homeland 11 months later. 

"Sadly, it took the grievous attack on 9/11 for us to collectively realize that al Qaeda presented a truly consequential threat to America’s security," Admiral Christopher W. Grady, now vice chairman of the Joint Chiefs of Staff and the nation's second-highest ranking military officer, wrote during a 20th anniversary retrospective of the attack.

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Grady commanded the USS Cole from 2003 to 2004.

The U.S Navy guided-missile destroyer was in the port of Aden to refuel when two men pulled up alongside the vessel in a motorboat, reportedly making friendly gestures to the American warship.

They then detonated 1,000 pounds of explosives. 

The blast and inferno devastated the Cole and its crew. 

In addition to the human carnage, the explosion blew a 40-foot hole through the ship's hull at the waterline. 

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"The Cole crew fought valiantly for more than 96 hours to rescue their shipmates and save their ship under extremely dangerous conditions," wrote Admiral Grady.

Reports said that 36 to 40 sailors were wounded. 

International allies rallied to the aid of the American sailors and the vessel. 

The HMS Marlborough was the first ship to arrive and offer aid. The French air force assisted evacuations. 

The USS Cole was repaired and returned to sea in 2003. 

It's still in service today.

Most of the sailors killed in the attack were in their teens or 20s. They hailed from across the nation and represented a broad cross-section of the American people. 

Those killed were the following individuals. 

Kenneth E. Clodfelter, 21, Mechanicsville, Virginia; Richard Costelow, 35, Morrisville, Pennsylvania.; Lakeina M. Francis, 19, Woodleaf, North Carolina; Timothy L. Gauna, 21, Rice, Texas; Cherone L. Gunn, 22, Rex, Georgia; James R. McDaniels, 19, Norfolk, Virginia; Marc I. Nieto, 24, Fond du Lac, Wisconsin; Ronald S. Owens, 24, Vero Beach, Florida; Lakiba N. Palmer, 22, San Diego, California; Joshua L. Parlett, 19, Churchville, Maryland; Patrick H. Roy, 19, Cornwall-on-Hudson, New York; Kevin S. Rux, 30, Portland, North Dakota.; Ronchester M. Santiago, 22, Kingsville, Texas; Timothy L. Saunders, 32, Ringgold, Virgina; Gary G. Swenchonis Jr., 26, Rockport, Texas; Andrew Triplett, 31, Macon, Mississippi.; and Craig B. Wibberley, 19, Williamsport, Maryland. 

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The sudden deaths of 17 brave young sailors were still not enough to raise greater awareness of the al-Qaeda threat, both among the American public and among government officials.

"As al-Qaeda threats to American interests multiplied in the late 1990s, U.S. government officials had various opportunities to act against Osama bin Laden," the 9/11 Memorial Museum noted. 

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"In 1998, a series of bombings in Afghanistan killed dozens of terrorists at training camps but missed bin Laden. That same year, an operation to capture bin Laden at the terrorist organization’s training camp and headquarters at Tarnak Farms was canceled due to concerns about civilian casualties and the mission’s legality."

The world was shocked out of its complacency on Sept. 11, 2001, with the Osama Bin Laden-led al-Qaeda terror attacks that killed 3,000 people and dramatically reshaped geopolitics. 

"The USS Cole bombing followed an unsuccessful attempt on January 3, 2000, to bomb another U.S. Navy ship, the USS The Sullivans," the FBI reported in its history of the attack. 

"In this earlier incident, the terrorist boat sank before the explosives could be detonated; however, the boat and the explosives were salvaged. The boat was then refitted, and the explosives were tested and reused in the USS Cole attack."

USS Cole sailors fought at the front lines of the War on Terror, without realizing it at the time.

"For the citizens of this great nation, know that I see reflections of the Cole heroes in today’s sailors," wrote Admiral Grady. 

"This gives me tremendous confidence that the American spirit is alive and well."