WASHINGTON (AFP) - The US military wants to revamp its nuclear arsenal and develop new low-yield atomic bombs, largely in response to Russian actions in recent years, the Pentagon says in a new policy statement.
The so-called Nuclear Posture Review, released on Friday (February 2), outlines the Pentagon's nuclear ambitions under President Donald Trump and is the first time since 2010 that the military has spelled out how it foresees nuclear threats in the coming decades.
It marks a sobering break from the vision for America's atomic future under former president Barack Obama, who during a famous speech in Prague in 2009 called for the elimination of nuclear weapons.
While the document underscores the administration's concerns about North Korea, Iran and China, the focus falls largely on Russia.
"This is a response to Russian expansion of their capability and the nature of their strategy and doctrine," Defence Secretary Jim Mattis wrote in the introduction to the 75-page document.
"These developments, coupled with Russia's seizure of Crimea and nuclear threats against our allies, mark Moscow's decided return to Great Power competition," he also wrote.
The Pentagon worries Russia assumes America's regular, large-yield weapons are essentially too big to ever be detonated, as their use would likely result in large-scale retaliation and wipe much of humanity off the map.
"There are strong indications that our current strategy posture and capabilities are perceived by the Russians as potentially inadequate to deter them," Mr Greg Weaver, the deputy director of strategic capabilities for the military's Joint Staff, told reporters.
"The US and NATO require a wider range of credible low-yield nuclear options to do a very specific thing: to convince the Russian leadership that if they initiate limited nuclear use, in a war with the alliance, our response will deny them the objective they seek and impose costs that far outweigh those benefits they can achieve," he added.
The document, an earlier version of which was leaked last month, says that by having more, smaller nukes the Pentagon can counter adversaries' "misperceptions" that the United States would not respond to another country using its own low-yield bomb.
The new strategy calls for a continuation of the nuclear modernisation programme ordered by Mr Obama that encompasses all pillars of the "triad" - ground-based intercontinental ballistic weapons, submarine-launched rockets and bombs delivered by plane.
But unlike the Obama strategy, which stressed reducing the role of nuclear weapons, the new policy has a more assertive tone.
Low-yield nuclear weapons, also known as "tactical" nukes, are still extremely powerful and can pack as much destructive punch as the bombs dropped on Hiroshima and Nagasaki at the end of World War II.
America already has a massive nuclear arsenal at its disposal, including 150 B-61 nukes stored across multiple European countries that can be configured for low-yield options.
The new weapons envisioned by the Pentagon would be launchable from submarines or ships, so would not need to be stockpiled in Europe.
They could also get around Russian air defences more easily.
The bombs would not add to America's nuclear horde, and would instead repurpose existing warheads, but critics say the Pentagon would be going against the spirit of non-proliferation agreements.
"We are on the cusp of a new era of nuclear proliferation," warned Mr Barry Blechman, co-founder of the Stimson Center, a nonpartisan anti-nuclear proliferation think tank in Washington.
"This is the great nuclear danger raised by the new" nuclear policy.
Weaver disputed media accounts that the nuclear posture review lowered the threshold for America to use nuclear weapons.
"The purpose of these capabilities is to make a US response to nuclear use more credible, not to make US first use more likely," he said.