Nuclear Stocks Sell Off Sharply as AI Trade Wobbles, China Security Concerns Deepen

Nuclear Stocks Sell Off Sharply as AI Trade Wobbles, China Security Concerns Deepen A bruising Monday session for small modular reactor names tests whether this year's extraordinary gains can hold as investors reassess the AI power thesis. Several nuclear sector names lost nearly 10% on Monday, snapping a run that has been one of the more remarkable energy equity stories of 2025. Oklo Inc., the Santa Clara-based advanced reactor developer, fell 9.38%, while SMR, based in Corvallis, Oregon, also dropped by more than 9% in the same session, according to TheStreet Pro data.⁴ The moves look dramatic in isolation. They look different against a longer backdrop. Oklo had gained 186% year-to-date before Monday's slide and 593% over the past twelve months. SMR had added 156% in 2025 and 310% over twelve months. At those valuations, a single-session correction of less than 10% is noise, not a trend shift, though it tests how deep the conviction actually runs among recent buyers.⁴ The sector draws much of its support from the AI power demand narrative, the idea that data centers will require firm, always-on generation that wind and solar cannot reliably provide. That thesis has already survived one sharp test: when DeepSeek's model efficiency news rattled AI infrastructure stocks earlier this year, nuclear names sold off hard. In retrospect, that was a buying opportunity, as several of these stocks subsequently recovered to post gains exceeding 100% year-to-date, TheStreet Pro noted.⁴ Not every name behaved the same way on Monday. BWX Technologies, the Lynchburg, Virginia-based company focused on naval nuclear propulsion and government contracts rather than commercial SMR development, fell just 1.8% in the session. Its relative resilience suggests the market is differentiating between pure-play AI power bets and more defensible industrial businesses with government contract visibility.⁴ Against that domestic equity backdrop, a separate and more structural China-related energy security story is gaining volume among European analysts. Speaking at the Solar 2026 seminar in Helsinki on Tuesday, an analyst told Montel that Europe's dependence on Chinese-manufactured solar components leaves the bloc's energy system exposed to deliberate attack. The specific concern is that components embedded in the grid could create vulnerabilities that could be exploited.² The worry is not purely theoretical. A UK security and defence think tank told Montel in a separate comment that Britain will need a coordinated response with allies to address threats posed by China across its energy supply chains, characterising it as the biggest challenge to UK energy security. The think tank stopped short of naming specific incidents or actors, but the message aligned closely with the Helsinki warning.¹ For European power traders, the solar security framing matters less as an immediate price catalyst and more as a slow-building regulatory risk. If EU or UK policymakers move toward mandating component diversification away from Chinese manufacturers, the cost implications for solar deployment timelines could be material. European solar build-out has been running at a pace that assumes Chinese panel and inverter supply chains remain intact and accessible.^2,1 The China angle also surfaces in oil markets, though from a different direction. PetroChina is currently trading at a valuation below the implied worth of its proved reserves, Bloomberg reported, a discount that reflects a range of investor concerns including governance, capital allocation, and state control priorities that do not necessarily align with shareholder value maximisation.³ For traders, the immediate signal to watch in the nuclear space is whether Monday's drop holds or reverses. The AI power demand thesis has not changed. What has changed is that several of these names are no longer cheap on any conventional metric after this year's runs, and any softening in hyperscaler capital expenditure guidance or grid interconnection news could amplify the next sell-off. In Europe, the more pressing watch-point is whether the security warnings from Helsinki and London translate into legislative action before the end of the year. If they do, the economics of European solar expansion change significantly and quickly.^4,2,1