SEOUL—To see the future of American shipbuilding, Sen. Dave McCormick, a Pennsylvania Republican who is spearheading a push to bring naval manufacturing back to the U.S., had to venture half a world away.FILE A plane flies behind the National Security Multi-Mission Vessel (NSMV) "State of Maine", at the Hanwha Philly Shipyard in Philadelphia, Pennsylvania, U.S.

August 26, 2025. (REUTERS)McCormick, who has co-sponsored the bipartisan “Ships for America Act,” recently visited the main shipyard of South Korea’s Hanwha Ocean—a site bigger and more technologically advanced than any facility in the U.S.Four massive Goliath cranes grabbed hulking ship components. Automated plasma torches cut thick slabs of steel.

Bright orange robotic arms fastened bolts onto engine manifolds, pipe flanges and pump housings.President Trump has called for a new “Maritime Golden Age” by expanding American shipbuilding capacity. But the U.S. needs help from allies to pull off the turnaround.

And America’s most ambitious project to date involves Hanwha, which purchased a shipyard in Philadelphia about two years ago.During his recent shipyard visit, McCormick was shown a photo of modern welding machines delivered to Philadelphia, replacing decades-old equipment. A former U.S.

Army captain and hedge-fund executive, McCormick said the U.S. has lost its shipbuilding capacity in a generation—and needs a jolt to get naval manufacturing back on track.“The world is not going to wait for us to get there,” said McCormick, who was elected in 2024. “We need to move faster.”Hanwha and South Korea, for now, represent the clearest outside efforts to spur an American shipbuilding revival. Hanwha has spent around $350 million since its December 2024 acquisition to upgrade the Philadelphia site and plans to spend billions more.

The company has approved another $400 million in investments now through the end of next year.The South Korean government, as part of its trade deal last year with Trump, has pledged $150 billion to improve U.S. shipbuilding.On Thursday, HD Hyundai, a major Korean shipbuilder, created a joint venture with Kiewit, an American construction company, to build an advanced U.S. shipyard starting from next year with full-scale operations targeted by 2029. Financial terms and the specific location of the planned site weren’t disclosed.A broader boost is needed.

The U.S. makes less than 1% of the world’s ships today. China, by far the world’s largest producer, boasts more than 230 times the shipping capacity of the U.S.China is expected to reel in more than three-quarters of new commercial ship orders this year, based on tonnage, according to Clarksons Research, with South Korea No.

2 at roughly 16%. No other country has more than 3%.The White House has proposed major overhauls to how the Navy designs, manufactures and maintains its fleet.

Under current U.S. law, naval vessels, with few exceptions, must be manufactured in the U.S. The Trump administration has recommended allowing foreign shipyards that make “substantial and durable” investments into the U.S. be allowed to make up to two naval ships in their home countries.

America’s commercial building sector is “not globally competitive” and the industrial base “atrophied,” said a White House statement in August.Hanwha is the only foreign firm to have acquired a U.S. shipyard in recent years. A big sticking point for other South Korean firms, as well as the Japanese and Washington’s other shipbuilding allies, is whether they can count on future demand from the Pentagon.

Congress has yet to pass the annual defense bill that would greenlight funding.In its version of the defense bill, the House, seeking to stymie potential workarounds, would block funds for any battle-force ships made in foreign shipyards. The Senate’s version includes a proposed amendment granting limited authority to use treaty allies’ shipyards for certain noncombatant ships.Due to higher production costs and a lack of suppliers, the U.S. will struggle to become a viable source of commercial ships, said Woo Jong-hun, a ship-production engineering professor at Seoul National University who works with Korea’s big shipbuilders.

And for military vessels, he said, restrictions limit the market and make the business case to a private company unclear.“No industry in the world has ever been revived through protectionism,” Woo said.Hanwha has nonetheless chosen to forge ahead. In August, it made a nonbinding offer valued at more than $1 billion to buy Austal USA’s shipyard in Mobile, Ala.

Talks remain ongoing.Hanwha has faced challenges in Philadelphia, in part due to higher costs, hiring limits and physical space constraints. But last month, it agreed with local authorities to expand the facility’s footprint by 40%, or nearly 50 acres, for a new training center and to undertake other upgrades that will expand capacity.In March, Hanwha won its first project with the U.S.

Navy, for subcontracting work to help with a preliminary design for a next-generation logistics ship. Then earlier this month, the company, alongside a Florida-based ship-management firm, was tapped to make a specialized auxiliary ship, with an option to build three more, for Trump’s planned “Golden Dome” missile-defense system.

The White House said the entire contract could reach $2 billion.Philly Shipyard is equipped to make the naval auxiliary vessels now and aims to have fully certified facilities to build combatant ships by 2028. The goal now is to land more Pentagon orders, said Alex Wong, global chief strategy officer at the Hanwha conglomerate, who focuses on defense initiatives in the U.S. and elsewhere.“Side by side, commercial yard and naval yard,” Wong said. “That’s the next step.”This year, several senior Trump administration and Pentagon officials have visited Philly Shipyard, including acting Secretary of the Navy Hung Cao and Transportation Secretary Sean Duffy.Modernizing the site will be necessary if Hanwha succeeds in landing more U.S.

Navy orders.In the coming months, trainees will be able to learn blasting and painting with virtual-reality equipment sent from South Korea—which lowers costs and exposure to hazardous fumes. By next year, Philadelphia will get dozens more welding carriages, allowing Hanwha to hire bigger groups of workers.

Some collaborative robots, or “cobots,” used at Hanwha’s Korea shipyard are expected to be installed in Philadelphia next year.McCormick, who has proposed several shipbuilding bills with Democrats, has pushed for refurbishing existing U.S. shipyards and building brand-new facilities. But first, companies need more certainty that naval orders will actually emerge.“If we’re going to get serious about shipbuilding, we’re going to have to make long-term commitments,” McCormick said.Write to Timothy W.

Martin at Timothy.Martin@wsj.com