A $20 million, 12,000-square-foot USS Bowfin submarine museum opened Monday with a new name and striking look that charts the course of Navy undersea duty, from the loss of the USS F-4’s 21 hands off Honolulu in 1915 up through the newest $6.5 billion Columbia-class ballistic missile submarines.

The first thing museumgoers see — and walk through — is a mammoth 43-foot-diameter ring that replicates the hull dimension of the new Columbia class, the largest submarines ever built by the United States.

Also visible is the new name — Pacific Fleet Submarine Museum — reflecting the goal of telling the wider story of Navy submarining beyond the resident Bowfin, nicknamed the “Pearl Harbor Avenger.”

Launched on Dec. 7, 1942 — a year after Japan’s attack on Oahu — the Bowfin conducted nine war patrols. The submarine itself and retail shop remained open as much as possible while the museum was closed for reconstruction.

In recent years the nonprofit museum — one of four at Pearl Harbor — has weathered government shutdowns, hurricane warnings, a failed landing dock at the adjacent USS Arizona Memorial that drove visitors away and, for the past year, COVID-19 closures and restrictions.

Retired sub skipper Chuck Merkel, the museum’s executive director, is relieved that the rebuilt museum is open, and optimistic about its future. A formal ceremony will be held next week.

With COVID-19 vaccinations ramping up, this summer — one of the peak travel times — will be telling.

“I don’t know that (visitation) is going to reach what it was pre-COVID, but I think it’s going to trend in the right direction,” Merkel said.

Longer term, “I think we’re going to be OK,” he said. The museum was prudent in the use of savings, and “we’ve got money that we’ve set aside for a rainy day and we’re going to be all right,” he said. That’s with “a lot of belt-tightening” and all salaried employees taking pay cuts, he said.

The renovated and enlarged museum includes three main galleries, which focus on the submarine force of World War II, the Cold War and the force of today and into the future.

The sub force wasn’t hit on Dec. 7, 1941, and was quick to go on the offensive. Information panels note that the USS Swordfish sank the Atsutasan Maru in the South China Sea nine days after Pearl Harbor.

But the Pacific submarine force struggled with risk- avoidance strategy and defective torpedoes until younger submariners stepped up.

The USS Wahoo became one of the most successful wartime submarines under commanding officer Dudley “Mush” Morton, described as fearless, aggressive and competent.

“Great Lord, I thought, we’re under the control of a madman!” Lt. George Grider is cited as saying in response to a bold order from Morton.

The Wahoo disappeared without a trace on Oct. 11, 1943, in northern Japan following air and sea attack.

A battle flag hand-sewn by Morton shows an American Indian profile with each of 19 headdress feathers representing an enemy ship destroyed.

A steam-driven 20-foot Mark 14 torpedo that was carried on a Bowfin war patrol is now decommissioned, with a graphic on one side revealing its internal components, including a big pressurized air tank.

On one wall is a large blowup of a Bowfin crew photo at Pearl Harbor after the submarine, with a pressure hull maximum diameter of 16 feet, left on a patrol and then returned when Japan surrendered in 1945.

A half-dozen or more subs are shown tied up in Pearl Harbor behind the Bowfin. “You can imagine how crowded Pearl Harbor was,” Merkel said.

Making his way through the World War II section, Ron Freiheit, 65, said the museum is “really well done.”

The Owatonna, Minn., resident escaped minus 30-degree temperatures back home during a weeklong contracting job at the Marine Corps base.

“It’s all great,” he said of the new museum. “I’m kind of a computer geek, so the computer over there for setting the torpedoes is just amazing to look at, and then the stories of all the submariners are really interesting.”

The bulky analog targeting computer, nearly as tall as a person and several feet wide, bristles with dials and knobs.

Merkel said submarine-launched ballistic missiles were influenced by Japan’s big aircraft-carrying submarines — some of which were returned to Pearl Harbor after the war and later sunk off Barbers Point.

“We took that hangar technology” and combined it with German V-1 missile technology, Merkel said. “That’s how we developed the Regulus missile” that was launched by submarines, he said.

The state of Hawaii is represented with ship items and a model of the ballistic missile submarine USS Kamehameha, later converted to carry special operations troops, and surfboards from the USS Honolulu, including one that made a visit to the Arctic.

A collage reveals the names and/or photos of the more than 4,000 men who died in the sub force since its inception in 1900, Merkel said.

Merkel said the new museum will open people’s eyes a bit more to the length and breadth of the “silent service’s” contributions — even though most missions remain classified.

Submarine ballistic missile nuclear deterrence missions remain a top priority, Merkel said, yet few realize that U.S. ballistic missile submarines have been on patrol every day since 1960.