A suspected U.S. submarine launched a Trident II D5 missile in the North Atlantic on September 21, 2025, in an event widely observed from Puerto Rico.
Several videos posted online captured the bright trail of a ballistic missile crossing the night sky over Puerto Rico on September 21. Analysts believe the launch originated from a U.S. or British submarine operating in the North Atlantic and that the missile was a UGM-133 Trident II D5, a nuclear-capable system deployed only by the U.S. Navy and the British Royal Navy. The launch has not been officially confirmed, but its timing is notable as it comes amid heightened U.S.–Venezuela tensions and intensifying nuclear competition with Russia and China.
The Trident II D5 remains the backbone of the U.S. and U.K. sea-based deterrent. Designed by Lockheed Martin, it is a three-stage missile powered by solid fuel, weighing nearly 59 tons at launch and stretching 13.42 meters in length with a diameter of 2.11 meters. It can carry a payload of up to 2,800 kilograms and uses a Post-Boost Vehicle that can release as many as twelve independently targetable reentry vehicles. In practice, arms control treaties reduce the number to eight. Warheads include the W76 at 100 kilotons, the more powerful W88 at 475 kilotons, and since 2020, the W76-2, a lower-yield option meant for limited scenarios. The guidance package combines inertial navigation with stellar referencing and achieves an accuracy of roughly 90 meters CEP, enough precision to target hardened facilities.
The missile force is distributed across the fleets of the two countries. The U.S. Navy deploys Trident D5s aboard fourteen Ohio-class submarines, each carrying twenty missiles, for a total of 240. The Royal Navy operates four Vanguard-class boats, with sixteen missiles apiece. That arrangement goes back to the 1963 Polaris Agreement, which allowed London to acquire U.S. missile technology while maintaining its independent deterrent. Continuous patrols at sea are the principle: one submarine always on station, guaranteeing the second-strike capability at the core of nuclear deterrence. The Trident D5’s range, from 2,000 to 12,000 kilometers, covers every conceivable target. Yet the latest videos have raised the possibility that this test carried something unusual, possibly a hypersonic glide vehicle under evaluation. If so, that would mark an important development in defeating modern missile defenses.
Operationally, the system offers what strategists prize most: survivability. Submarines armed with Tridents are difficult to detect and track, making preemptive strikes nearly impossible. They form the most secure leg of the American nuclear triad, ensuring that even in the event of a first strike, retaliation would follow. This logic explains why both Washington and London continue to extend the program. The original Life Extension program began in 2002. A second phase, Life Extension 2, was awarded in 2025, with Lockheed Martin receiving a 383 million dollar contract. The updated missiles will arm the new Columbia-class submarines in the U.S. fleet and the Dreadnought-class in Britain, expected to serve well into the 2080s.
According to some Russian sources, the September 21 launch may not have been a routine reliability test but instead involved an “unusual payload,” possibly a hypersonic glide vehicle. Such a system, if confirmed, would mark a departure from the traditional configuration of the Trident II D5, which normally carries reentry vehicles on a predictable ballistic path. A hypersonic glide vehicle separates from the booster at high altitude and then maneuvers through the atmosphere at speeds above Mach 5, making interception by missile defenses far more difficult. Another possibility is that the missile carried a modified test payload designed to simulate advanced countermeasures or to trial guidance improvements. Both scenarios would signal Washington’s intent to adapt its submarine-based deterrent to overcome the growing capabilities of Russian and Chinese missile defense systems, reinforcing the impression that the Atlantic launch was more than a simple exercise.
The geopolitical context compels Washington and London to sustain this level of readiness. Russia retains a diversified strategic force and regularly signals its nuclear posture, while China is accelerating its nuclear buildup, with an arsenal expected to reach 1,500 warheads by 2035. Beijing is also developing new intercontinental strike capabilities, including large numbers of missile silos and hypersonic systems. In this emerging tripolar environment, where Moscow and Beijing increasingly coordinate their positions, the United States faces a “two-peer challenge”: deterring both Russia and China, each capable of directly contesting its strategic superiority. This shift undermines the bilateral logic inherited from the Cold War and increases pressure on European and Atlantic allies, who rely heavily on U.S. nuclear deterrence.
Within this global framework, the Caribbean region has become a secondary but symbolically significant theater. The decision to conduct a launch in the North Atlantic, so close that its trajectory was visible from Puerto Rico, comes as Washington intensifies pressure on Caracas, Moscow’s main regional ally and a key partner for Beijing within the Belt and Road Initiative. Venezuela has acquired nearly $10 billion worth of Russian weaponry, including S-300 air defense systems, and continues to receive Moscow’s political backing at the United Nations. Beijing, for its part, has invested billions in Venezuelan infrastructure and energy, consolidating its economic and diplomatic presence. Cuba and Nicaragua also serve as points of support for both Eurasian powers, through military agreements with Moscow and technological cooperation with Beijing.
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