More than 2,000 people were on Pearl Harbor’s Pier Kilo 10 on Saturday to honor Dec. 7, 1941, hero John Finn and the $2 billion destroyer named for him at a commissioning ceremony marking the warship’s entry into active service.

During the first attack by Japanese airplanes on Naval Air Station Kaneohe Bay, Finn, who was at home on base and about to have coffee with his wife, raced to his squadron and started firing back with a .50-caliber machine gun mounted on a tripod on an exposed portion of aircraft parking ramp.

The chief aviation ordnanceman received 21 shrapnel and bullet wounds from the strafing planes but kept firing, leaving only when ordered to receive medical attention. Following first aid, and in pain, he returned to his squadron area to supervise the rearming of returning American planes.

Finn’s bravery earned him the first Medal of Honor of World War II, presented by Adm. Chester Nimitz on Sept. 14, 1942, aboard the USS Enterprise. Nimitz said Finn displayed “magnificent courage in the face of almost certain death” during the attack on Pearl Harbor.

Joe Finn, 74, said after the commissioning that he wished his father, who died at age 100 in 2010, could have been there.

“He had a real charisma. He met all kinds of people. He met all the presidents since Eisenhower,” the San Diego man said. “He loved to talk, and he was really good at it.”

More than 50 family members came in from states including California, Oregon, Washington, Arizona and Florida.

Navy Lt. Caleb Nation, whose grandmother was Finn’s first cousin, didn’t have to come far; the 41-year-old aviation maintenance officer is with Helicopter Maritime Strike Squadron 37 at Kaneohe Bay and works in the “same hangar John Finn fought in,” Hangar 3, he said.

“Back around ’05 through ’08 he would come out every year for the Pearl Harbor anniversary,” Nation said. “He’d come stay with me and visit. We’d walk the flight line together. He pointed out every bullet hole, everything you could imagine.”

Finn was the ordnance officer for Patrol Squadron 14 and when he got to the hangar “he saw one of the painters out there trying to desperately fight back and shoot down the Zeroes,” Nation said. “And John Finn ran up to him and said, ‘Hey, Alex, no offense, but I can shoot a gun better than a painter,’ so John relieved him from those duties, and the rest is history.”

The 509-foot USS John Finn, with a core crew of 350, will be based in San Diego. Laura Stavridis, whose husband is retired Adm. Jim Stavridis, former supreme allied commander for Europe, is the ship’s sponsor. On Saturday, in a time-honored tradition, Laura Stavridis gave the order, “Officers and crew of the USS John Finn, man our ship and bring her to life!”

With that, the crew ran aboard the ship, decorated with red, white and blue banners, as the Pacific Fleet Band played “Anchors Aweigh,” the Navy song. The crew then fired up the engines and blasted horns and sirens.

Laura Stavridis said the John Finn crew can take strength from the courage of the ship’s namesake as it undertakes its own dangerous missions — whether that is off North Korea defending against ballistic missiles, launching Tomahawk missiles in the Middle East, or conducting a freedom of navigation patrol in the South China Sea.

The ship is the 63rd Arleigh Burke-class destroyer and the first of what’s known as the DDG-51 Flight IIA “restart” ships — so called because the Navy restarted the Arleigh Burke line after the Zumwalt-class of destroyers was stopped at three ships due to prohibitive costs.

The John Finn, whose motto is “Stand Fast and Fight,” has Aegis Baseline 9 combat system upgrades with integrated air and missile defense that allows it to conduct ballistic missile defense and anti-air warfare at the same time.

“As North Korea’s recent (intercontinental ballistic missile) test demonstrates, as Chinese and Russian aggressiveness grows, as ISIS tries to gain a foothold in our region, the USS John Finn couldn’t come to the Indo-Asia-Pacific at a more pivotal moment in our nation’s history,” said Adm. Harry Harris, commander of U.S. Pacific Command.