The US Navy is planning to convene a conference in San Diego this summer to discuss its most dangerous adversary: rust.

In June, the American Society of Naval Engineers will hold a seminar that looks at potentially one of the greatest threats to the United States Navy—and, for that matter, all the navies of the world.

That threat isn’t sea mines, land-based anti-ship missiles, or even nuclear-powered submarines. Those threats are all real and need to be taken seriously, of course. However, there is a single, far more debilitating threat, and one that American sailors ignore at their peril.

Rust: The Worst Four-Letter Word in the US Navy

The greatest threat to the US Navy is rust—the constant corrosion of steel hulls upon contact with water, a problem that has bedeviled seamen for centuries.

“Corrosion is a major factor in the readiness and total ownership cost of naval systems and this conference is intended to provide updated information on programs, policies, standards and Fleet experience related to corrosion and to promote discussion and sharing of information on technologies and strategies for controlling corrosion,” the American Society of Naval Engineers explained, promoting the upcoming “MegaRust” conference in San Diego.

“MegaRust” is a name that sounds like an anime villain, but the issue is very serious. It has become such a problem for the Navy that it even drew attention—and public criticism—from President Donald Trump last year.

In April 2025, Trump reportedly gave then-Secretary of the Navy John Phelan a direct order to “fix the damn rust” conspicuously covering many Navy ships. The reality TV star-turned-president is well-known for his close attention to appearances, but the nature of the order seemed to suggest he didn’t quite understand that rust isn’t something that can be permanently “fixed.”

The issue began after Senator Rick Scott (R-Fla.) showed the president a photo of the Arleigh Burke-class guided-missile destroyer USS Dewey (DDG-105) caked in rust as the warship arrived in Singapore. Instead of evoking the “Great White Fleet” that President Theodore Roosevelt once ordered to sail around the world to showcase American strength, DDG-105 seemed to suggest that the US Navy was a rusting shell of its former self.

When photos of USS Dewey covered in rust caught Trump’s attention, he told Phelan to address the issue—allegedly using language that a sailor would find very familiar.

Mark Lattner, director of the US Navy’s Ship Integrity and Performance Engineering, Naval Systems Engineering Directorate, was charged with addressing the issues. In January, at the Surface Navy Association’s annual symposium, he presented some solutions, including polysiloxane paint, originally developed to counter graffiti. Other options included using composite materials—notably stainless steel rather than traditional steel—in hull construction.

Rust Is Mostly Just Ugly—but Can Be Dangerous, Too

Rust remains the slow but serious enemy of warships, particularly retired museum ships without access to the Pentagon’s tremendous cash flow. Much effort has been placed on preserving the battleship USS Texas (BB-35) and all four Iowa-class battlewagons. Years were spent patching holes in the hull of BB-35 in Texas, and the USS New Jersey (BB-62) spent the spring of 2024 undergoing a scraping and painting of her hull at the Philadelphia Naval Yard.

The issue for the US Navy’s active warships is that they spend far longer at sea, which allows the rust to build up.

“Maintenance is an issue for all steel vessels. When paint coatings are damaged or removed by impact rusting, it is almost certain to commence quickly,” explained Robert E. Melchers, emeritus professor of civil engineering at the University of Newcastle in Australia and an expert on marine corrosion.

Melchers told The National Interest that the rust stains on some ships often aren’t as serious as they look, with an outward appearance that is “far worse than it is from a structural/safety point of view.” This has sometimes led the US Navy to pragmatically put off rust removal efforts in favor of more critical issues, which has contributed to the fleet’s shabby appearance.

The issue isn’t worse in any particular part of the world. Seawater is seawater everywhere, regardless of the region.

“Sure, local conditions may play a part—the most important is increased temperature—it increases corrosion, but not all that much for normal ships’ hulls and superstructures,” added Melchers. “Seawaters around the world are relatively similar otherwise.”

Waters that are subject to “hard water inflow,” notably near certain river mouths and coastal areas, are marginally less corrosive. US Navy warships are not usually in such places for very long; museum ships usually are, giving them a small measure of protection from the worst effects.

“Conversely, heavily polluted seaways, such as those typical of many harbors, may encourage microbiological activity resulting in increased corrosion,” Melchers continued. He noted in a paper that US warships often spend more time in heavily-trafficked and polluted ports than in the open water, exacerbating the issue.

From a safety perspective, surface rust like that on the USS Dewey is often secondary to rust on parts of the ship that are not outwardly visible.

“A potentially serious problem is corrosion in ballast tanks, particularly for older vessels and those not well maintained internally,” warned Melcher. “Out of sight, out of mind. Of course, this is not visible to the outside world.”

The Only Real Solution to the Rust Problem Is Regular Maintenance

The issue isn’t going to go away, especially as the US Navy is getting smaller, at least potentially in the number of sailors in uniforms. Warships may become more automated, meaning smaller crews—and fewer hands to conduct maintenance—so the Navy may soon need to develop hull-scraping robots and drones that can paint the ship.

“With the Navy trying to operate ships with smaller crews, you lack the spare hands to apply paint,” suggested Dr. David Winkler, distinguished historian of maritime and naval history and a retired US Navy commander.

In his book on the history of the US Navy’s first aircraft carrier, the USS Langley (CV-1), Winkler explained that upon return to drydock, the crew scraped off months of marine growth and other sediments, using just wire brushes. The hull was prepared for paint coating, with scraping beginning at noon and continuing until dark.

During deployments, the US Navy has historically had foreign workers handle some of the maintenance. A combination of enhanced security requirements, environmental regulations, and a shift in maintenance strategies that prioritize long-term, specialized care over ad hoc cleaning have all contributed to a decrease in the practice.

“It used to be you could pull into foreign ports where labor was cheap, and you could get a quick make-over,” Winkler told The National Interest. “Those opportunities are rather limited nowadays.”

Director Lattner has said that new technology is being developed, and contractors are now being charged with doing the work sailors used to take on.

New procedures could help, and Melchers said the issue is more than just scraping and painting.

“Choice of paints, or protective coatings, tends to be less of an issue compared with thoroughness of surface preparation prior to application of the paint,” Melchers explained. “Modern shipbuilding does a lot of painting and assembly indoors, and for smaller vessels, this can also be the case for maintenance.”

About the Author: Peter Suciu

Peter Suciu has contributed to dozens of newspapers, magazines and websites over a 30-year career in journalism. He regularly writes about military hardware, firearms history, cybersecurity, politics, and international affairs. Peter is also a contributing writer for Forbes and Clearance Jobs. He is based in Michigan. You can follow him on Twitter: @PeterSuciu. You can email the author: Editor@nationalinterest.org.

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