Bulletin of the Atomic Scientists: The belief that the US is the only declared nuclear power that isn’t modernizing its nuclear arsenal is fast becoming an article of faith in nuclear weapon policy circles, says Kingston Reif in the Bulletin.
From this belief arises a dangerous argument: US allies and adversaries are adding new nuclear weapons and capabilities, while Washington is allowing its nuclear forces to atrophy. Opponents of President Barack Obama’s nonproliferation and disarmament agendas are using this idea as a way of undermining his plans, alleging that by not modernizing, the US is in danger of being surpassed by Russia and China. Yet these arguments are specious and misleading.By narrowly defining “modernization” as the production and deployment of new warheads and delivery vehicles, an inappropriate standard is set by which to judge the health of a nuclear arsenal. What matters far more than the age of warheads and other equipment is whether a country has a reliable, credible deterrent. Viewed in this light, the US cannot be said to be falling behind: Washington takes continual steps to ensure that its arsenal remains dominant, and indeed, its nuclear arsenal remains second to none.
The finding that the Saturnian moon may host layers of icy slush instead of a global ocean could change how planetary scientists think about other icy moons as well.
Modeling the shapes of tree branches, neurons, and blood vessels is a thorny problem, but researchers have just discovered that much of the math has already been done.
January 29, 2026 12:52 PM
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