This is The DEFCON Warning System. Alert status for 1300 UTC, Monday, 13th October 2025:
Condition Green – DEFCON 5.
There are currently no imminent nuclear threats at this time.
Russia’s Warning Over U.S. Tomahawks in Ukraine
In the past week, Russia escalated its rhetoric in response to U.S. discussion around providing long-range Tomahawk cruise missiles to Ukraine. Former Russian President Dmitry Medvedev warned publicly that the use of Tomahawks—if supplied by Washington—“could end badly for everyone, especially Trump.” [1]
Medvedev’s main point: once in flight, one cannot distinguish a Tomahawk armed with a conventional warhead from one carrying a nuclear warhead. [2] He implied that such ambiguity might compel Russia to take nuclear escalation seriously.
The Kremlin, too, expressed “extreme concern” at the possibility, warning that the conflict had reached a “dramatic moment” of escalation. [3] Russian President Putin echoed that supplying such missiles would damage U.S.-Russia relations deeply. [4]
From the U.S. side, President Trump has stated he is considering approving the transfer via NATO, rather than a direct bilateral sale, and that assurances would be required about their use. [5] Ukrainian President Zelensky has publicly pledged that any such missiles would be used strictly for military targets, not on civilians. [6]
This is a classic example of escalation through ambiguity. Russia is signaling that if the U.S. introduces systems capable of striking deep into Russian territory, Moscow may feel compelled to respond more aggressively—not necessarily with immediate use, but by shifting to higher readiness, heightened alert, or even deployment of deterrent forces.
Even without actual nuclear use, threatening the possibility can raise tension, reduce strategic options, and risk accidents or miscalculations. The fact that Tomahawks are dual-capable in doctrine (in U.S. planning, in theoretical conversions) is precisely what Russia is leveraging rhetorically. If the U.S. does provide Tomahawks, Russia may accelerate deployment of air defenses, counterstrike planning, or further reliance on escalation contingencies. It becomes a test of resolve. Does the U.S./NATO believe Russia would cross a nuclear threshold in this conflict? Do they believe their deterrence is sufficient?
In short: this is a red-line gambit by Moscow, testing how far Washington is willing to push in Ukraine without triggering an even fiercer response.
Russia Withdraws from the Plutonium Management and Disposition Agreement
On 8 October 2025, Russia’s lower house of parliament approved withdrawal from the Plutonium Management and Disposition Agreement (PMDA) with the United States. [7] Under the original terms, both nations committed to disposing of 34 tonnes of weapons-grade plutonium—enough for tens of thousands of warheads—by converting or irradiating it to less dangerous forms. [8]
Russia cited recent U.S. strategic moves—sanctions, NATO expansion, changes in plutonium disposition methods—as upsetting the balance of the agreement. [9] Notably, Moscow had already suspended active participation in 2016 and had criticized U.S. diversion of plutonium into diluted forms rather than original agreed methods. [10]
This is a setback to nuclear arms control architecture. The PMDA was one of the few remaining bilateral frameworks for fissile material management. Russia’s withdrawal signals that it sees less strategic utility in cooperative arms control, especially in a climate of confrontation. It raises the possibility that Moscow may retain or redeploy plutonium in military roles or at least keep it as a latent stockpile. That increases ambiguity and lowers the barrier to re-mobilization. For Washington and other states, it signals that mutual trust in material controls is deteriorating. This also ties into shifts in broader arms control regimes: as New START approaches expiration, as other treaties collapse, we may see a more fragmented and perilous nuclear order.
NATO’s Steadfast Noon Nuclear Exercise
On 10 October 2025, NATO announced its annual nuclear exercise, named Steadfast Noon, would begin on 13 October. [11] These exercises test readiness, interoperability, command and control, and tactical procedures for alliance nuclear operations. [12]
Though routine in nature, the exercise occurs at a sensitive moment: amid rising tensions over Ukraine, Russia’s new posture on plutonium, and sharp Russian rhetoric over Tomahawk missiles.
North Korea’s Parade and Missile Advances
On 9 October, North Korea conducted a grand military parade in Pyongyang to showcase its latest weapons systems. [13] Key highlights included promotion of a new Hwasong-20 solid-fuel intercontinental ballistic missile (ICBM), hypersonic glide vehicles, and striking visual displays of drone, missile, and strategic systems. [14]
Analysts interpret this as more than domestic signalling—it reinforces Pyongyang’s posture as a nuclear power with strategic reach, aligned with global challengers (Russia, China) against Western power. [15] The regime also publicly acknowledged its fighters in Russia’s Kursk region, confirming direct military involvement in the Ukraine theatre. [16]
This show North Korea continuing to expand its nuclear–missile threshold and is not hiding ambitions to threaten distant adversaries. The regime is sending a message of deterrence, projecting that any intervention against it comes with risk. Its statements and display reinforce its strategic alignment with Russia and China—not just regionally but in the broader anti-Western posture. For Asian states, this heightens urgency in missile defense, warhead posture, and deterrence arrangements (e.g. U.S.–Japan–South Korea coordination). Importantly, even as the West’s attention is on Europe, the Korean Peninsula remains a locus of nuclear risk escalation.
Russian Statements on Arms Race and Treaty Breakdown
President Putin recently declared that if New START is not extended, Russia is prepared to match U.S. nuclear build-up. He also warned that other states, emboldened by the unraveling of arms control, might begin testing nuclear weapons. [17]
In multilateral forums, Russia has resisted proposals for stricter limits on sub-strategic nuclear weapons, broader missile defense constraints, or new verification mechanisms. [18] Moscow is increasingly framing arms control as a zero-sum domain, one where confidence has eroded.
The interpretation of Russia’s statements are that Russia is preparing for a post-arms-control era and wants to ensure parity or overmatch. Threats to test nukes suggest Moscow may seek to normalize testing revival or brinkmanship. And the collapse of verification regimes magnifies ambiguity and reduces mutual confidence, pushing states to harden their arsenals as insurance.
Strategic Tensions in U.S.–China Trade and Tech
Also in the last week, the U.S. and China escalated trade tensions. China imposed export restrictions on rare earth minerals—critical inputs for defense, electronics, and advanced weapon systems—framing them as national security controls. [19] The U.S. responded with threatened tariffs and new software export controls. [20] Such economic choke points have ripple effects into military supply chains, weapon development, and high-tech strategic competition.
From a DEFCON perspective: we are not at the brink, but the foundation of strategic stability is eroding. We must watch for sudden signals — missile deployments, ad hoc rule changes, crisis mis-management, or unexpected escalatory moves.
Conclusion
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The next scheduled update is 1350 hours, 20th October 2025. Additional updates will be made as the situation warrants, with more frequent updates at higher alert levels.
This concludes this report of the DEFCON Warning System.
