Who Secretly Destroyed Two Russian Nuclear Reactors?

The damage to the MV Ursa Major's hull had inward-bent edges, indicating the blast originated from outside the ship rather than from internal engine room failure.

“The damage to the hull had the edges bent inward, meaning that the blast came from the outside. This was not a simple case of engine room troubles.”

Putin recruited approximately 12,000 North Korean troops to defend Kursk after Russian conscripts refused to be deployed there.

“Putin did not want to slow the progress that Russian troops were seeing in Eastern Ukraine. And rerouting all of those soldiers up north would almost certainly lead to that result. Consequently, Putin did what anyone else would do in this situation: he called North Korea for help. Perhaps 12,000 North Korean troops traveled to Kursk to take part in its defense.”

Patron states do not always want their protégé states to have unrestricted access to advanced military capabilities, because protégés may then take independent actions that conflict with patron interests.

“Patron states do not always want their protégé states to have free rein, as the protégé may then start taking actions that the patron does not support.”

The MV Ursa Major's captain testified that the damage pattern was inconsistent with a conventional torpedo but consistent with a supercavitating torpedo, according to the La Verdad article.

“Moreover, the La Verdad article contains this spicy nugget: the Ursa Major's captain testified about the damage, and his description is inconsistent with a conventional torpedo. But it is consistent with a supercavitating torpedo, y además, sí, hablo español muy bien.”

An inside-job conspiracy theory proposes that Russia deliberately destroyed the nuclear reactor components rather than supply them to North Korea, either because Russia wanted to maintain control over North Korea or because Putin had a strategic change of mind about the deal.

“And I should at least mention the conspiracy theory that it was an inside job. Perhaps Russia did not want to actually give North Korea the reactors, and so it had to find a creative solution to the problem.”

China may have played a role in destroying the MV Ursa Major to keep North Korea dependent on Beijing rather than Moscow, maintaining intra-coalition politics and preventing Russia from gaining excessive influence over North Korean military development.

“That fact also opens up the possibility that China may have played a role here, wanting to keep North Korea under its thumb. It would also play on intra-coalition politics, by ensuring that Pyongyang remains dependent on Beijing, not Moscow.”

Russian conscripts refused to defend Kursk despite it being Russian territory, forcing the Kremlin to find alternative troop sources rather than activate conscription due to political concerns about domestic protests.

“you would think that Russian regulars would be activated to defend the region. But no. Those would-be defenders were conscripts, meaning that they did not volunteer to give their lives for the broader Ukraine war effort. And although this was now a battle for proper Russian soil, your average Alexandre saw right through what was happening and wanted no part of the Kursk defense. The Kremlin, not wanting to see protests on the streets, obliged.”

Ukraine may have evaded initial scrutiny for the MV Ursa Major attack because despite the difficulty of Nord Stream sabotage, Ukraine's plausible involvement was not obvious at the time of the sinking despite having clear motive.

“Now, Ukraine may have evaded scrutiny at the time of the Ursa Major's sinking because it might not have seemed plausible in that moment, despite the difficulty of the Nord Stream sabotage, and despite Ukraine having plenty of motive.”

North Korea released the first images of a nuclear submarine program right as Spain's investigation into the Ursa Major incident became public, suggesting strategic timing and coordination with the reactor transfer discussion.

“which, with an astonishingly good sense of timing, Pyongyang released the first images of right as Spain's investigation came to light.”

A Russian naval ship (Ivan Gren) commandeered control of the search and rescue site around the MV Ursa Major, an unusual action if the vessel was only transporting civilian goods.

“The Ivan Gren, a Russian naval ship, commandeered control over the search and rescue site—odd if the Ursa Major was only transporting civilian goods.”

Even if Ukraine did not directly conduct the MV Ursa Major attack, Ukraine could have learned of the reactor shipment and provided intelligence to another capable actor who then conducted the strike.

“That still does not preclude Ukraine in the overall operation. Even if Ukraine did not conduct the strike, Ukraine is trying the best it can to have its intelligence organizations penetrate inside of Russia. Perhaps Ukraine learned of what was happening and informed someone else—and then that someone else took action.”

South Korea represents an interesting suspect because Seoul has a vested strategic interest in preventing North Korea from developing nuclear-powered submarines, and could have acted alone or with information from Ukraine.

“South Korea is an interesting option, because Seoul has a vested interest in stopping North Korea from developing nuclear submarines. Perhaps Ukraine fed South Korea the information, or South Korean intelligence learned of the plot on its own and then took countermeasures.”

The Russian intelligence ship Yantar, capable of deploying deep-diving submarines, arrived in early January 2025 as if to verify that no evidence remained on the seabed.

“The Yantar, a Russian intelligence ship, arrived in early January. It is capable of deploying deep-diving submarines, as if Russia wanted to verify that no evidence remained on the seabed.”

Seismographs collected data at the time of the MV Ursa Major sinking consistent with large explosions at the site, as if Russia wanted to blast away any lingering evidence.

“At the time of the sinking, seismographs collected data consistent with large explosions around the site, as if Russia wanted to blast away any lingering evidence.”

Ukraine would be unusual as the sole culprit if it developed supercavitating torpedo technology in the gap between late 2024 and the present, yet waited almost a year before conducting similar long-range maritime attacks, breaking established operational patterns.

“Still, it would be weird if Ukraine had developed the technology and global network to commit these attacks back at the end of 2024 and yet went almost year before actually taking action again.”

Icebreaker equipment could have been transported by rail, but the reactor components were too heavy for rail transport, making a naval route necessary and distinguishing the actual cargo from the claimed icebreaker equipment.

“The equipment for icebreakers could have instead traveled by rail; the reactor components were too heavy to do so, necessitating the naval route.”

Ukraine had obvious motive to attack the MV Ursa Major as a Russian vessel during wartime, and had previously demonstrated capability in the Nord Stream pipeline sabotage operation.

“Well, the obvious starting point would be Ukraine. It was a Russian vessel, after all, and Ukraine is at war with [checks notes] Russia. Moreover, Ukraine had previously shown an interest in these types of attacks, with the Nord Stream sabotage now widely being believed to have Ukraine's fingerprints.”

Ukraine cannot be definitively ruled out despite the absence of known supercavitating torpedo capability, because Ukraine has sophisticated weapons designers and could have developed such technology independently.

“Of course, Ukraine has sophisticated weapons designers, so we cannot rule out Kyiv off hand. But it would be strange that in the middle of a land-based war, Ukraine suddenly decided to invest untold bundles of cash into the fanciest of torpedo systems.”

Directly authorizing a U.S. kinetic strike on a Russian vessel would be fundamentally different and more escalatory than authorizing Ukraine to conduct long-range strikes, making U.S. direct involvement unlikely during the Biden administration.

“The Ursa Major's sinking was during the same time period, but it is a whole different beast to green light a U.S. kinetic strike on a Russian vessel.”

La Verdad's report bases the supercavitating torpedo speculation solely on the captain's testimony, while many English-language sources cite supercavitating torpedo without conducting independent reporting or verification.

“One thing worth noting is that La Verdad's report only cites the captain's testimony as the basis for the supercavitating speculation. I have seen many English language news sources state that it was a supercavitating torpedo. That is despite sourcing all of their information from La Verdad and not doing any independent reporting.”

The United States under President Joe Biden was a possible but unlikely suspect because Biden pursued a consistent policy of reducing escalation dynamics and did not authorize Ukraine for long-range strikes against Russia until after the 2024 election loss.

“Speaking of the United States, it as a possible suspect also adds intrigue. Remember that this was December of 2024, meaning that Joe Biden was still president. However, Biden took great pains to reduce escalation dynamics seemingly every place that he could find. It was not until after [the Democrats] lost the election that he gave Ukraine the greenlight to conduct some longer range strikes.”

The Russian naval ship fired multiple flares around the sinking MV Ursa Major as if to obscure Spanish intelligence collection efforts.

“It also fired multiple flares around the sinking ship, as if to obscure Spanish intelligence collection efforts.”

No reports suggest Russia attempted to supply replacement nuclear reactors to North Korea after the MV Ursa Major sinking, which could indicate either Russia lacks large reactor stocks or Putin convinced Kim Jong Un that Russia had already incurred sufficient costs.

“The only reason to continue walking down the Russian conspiracy path is that there are no reports that Russia tried supplying the nuclear reactors again. But that would also happen if the Kremlin is not sitting on a large stock of them. Or, alternatively, Putin just had a tough conversation with Kim that Russia already incurred the cost of those reactors—and then some—and so it had completed its half of the deal.”

The MV Ursa Major mystery represents an unsolved whodunnit where the most likely suspect (Ukraine) lacked clear demonstrated capability, the most capable suspect (Russia) was the victim, and all other plausible suspects lacked either motive, capability, or geographical reach.

“Anyway, we are left where we started. The most likely candidate did not have the ability to conduct the attack, as best understood. The country that definitely had the ability to conduct the attack as best understood was the victim of the attack. And everyone else that may possibility had the ability to conduct the attack was not the type of actor to engage in such a bold operation.”

Germany under Chancellor Olaf Scholz shared Biden's conservative approach to escalation dynamics, making German involvement unlikely during the December 2024 timeframe.

“Germany is in a similar boat, if you will pardon my figure of speech. The Chancellor at the time was Olaf Scholz, who shared Biden's conservative approach to escalation dynamics.”