A new policy statement released by the Pentagon on Friday says that the U.S. must broaden its nuclear capabilities in response to a “rapid deterioration of the threat environment.”
The Nuclear Posture Review cites Russia as a particular threat, in line with the Pentagon shifting priorities from the fight against Islamist militants to “great power competition” with Moscow and Beijing.
“Our strategy will ensure Russia understands that any use of nuclear weapons, however limited, is unacceptable,” the document said.
The rationale for building up new nuclear capabilities, U.S. officials said, is that Russia currently perceives the United States’ nuclear posture and capabilities as inadequate.
Low-yield weapons
The U.S. will expand its capability by modifying “a small number” of existing long-range ballistic missiles carried by submarines to fit them with smaller-yield nuclear warheads. This will “ensure a prompt response option that is able to penetrate adversary defenses,” said the document.
Low-yield nuclear weapons, while still devastating, have a strength of less than 20 kilotons. The atomic bomb dropped on Hiroshima had about the same explosive power.
The argument for these weapons is that larger nuclear bombs are so catastrophic that they would never be used and do not work as an effective deterrent. With less power and destruction, the low-yield option would potentially be more likely to be used, serving as an effective deterrent.
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Not everyone buys this argument. “Even this term low-yield nuclear weapons, they’re not nuclear weapons you can use in a battlefield,” said Ray Acheson, a member of the advisory board of the International Campaign to Abolish Nuclear Weapons, which won the Nobel Peace Prize in 2017.
“These aren’t weapons that you can use to target a specific military facility. They’re weapons that are targeted at and would be used for destroying cities, civilian centres and infrastructure. They are not meant for a battlefield engagement or an actual war.”
Government officials said that adding to the U.S.’ low-yield capability would not increase the size of its nuclear stockpile. The document argues that by developing U.S. nuclear responses, it raises the Russian threshold for using the weapons, rather than lowering the U.S. threshold.
“To be clear, this is not intended to enable, nor does it enable, ‘nuclear war-fighting,’” says the document.
In the longer term, the U.S. will develop a nuclear-armed sea-launched cruise missile – a weapon that it had during the Cold War but was retired in 2011 by the Obama administration.
Jon Wolfsthal, a former top adviser to president Barack Obama on arms control, said there was a possibility that this could lead to a miscalculation.
“If we put nuclear weapons on cruise missiles and we launch conventional cruise missiles, how does Russia know that they are conventional?” he said.
When to use nuclear weapons
The policy also articulated that the U.S. would only use nuclear weapons “in extreme circumstances to defend the vital interests of the United States, its allies, and partners.”
The phrase “extreme circumstances” was used in the 2010 document put out by the Obama administration, but this latest edition goes into more detail on what the U.S. would consider “extreme.”
“Extreme circumstances could include significant non-nuclear strategic attacks. Significant non-nuclear strategic attacks include, but are not limited to, attacks on the U.S., allied, or partner civilian population or infrastructure, and attacks on U.S. or allied nuclear forces, their command and control, or warning and attack assessment capabilities,” it said.
“It seems to envision the use of nuclear weapons in a much broader range of circumstances,” said Acheson.
She thinks that this policy, emphasizing that nuclear weapons are an essential part of U.S. security, will lead to more proliferation. “Unfortunately, the message that is passing to the rest of the world is: if nuclear weapons are essential for your security, aren’t they also essential for ours?”
“As long as that image is projected, that nuclear weapons offer some form of security, then you’re going to see countries like North Korea trying to acquire nuclear weapons, or other countries.”
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Kingston Reif, director for disarmament research at the Arms Control Association advocacy group, said the document could bolster a new kind of arms race.
“It’s not an arms race in terms of numbers like during the Cold War, but is an arms race that involves more than just the United States and Russia and it involves upgrading and improving the capability of existing nuclear forces,” Reif said.
U.S. President Donald Trump said in a statement that the strategy will address the “wide array” of threats in the 21st century. “The strategy develops capabilities aimed at making use of nuclear weapons less likely. It enhances deterrence of strategic attacks against our Nation, and our allies and partners, that may not come in the form of nuclear weapons.”
Acheson said that the existence of nuclear weapons poses a massive risk to humanity. “If nuclear weapons are used again, we’re going to see catastrophic humanitarian consequences. We’re going to see the destruction of cities. We’re going to see millions of human beings die,” she said.
“These are catastrophic consequences that will change civilization as we know it, that will change global economies, that will undermine everything that we have built as human society.”
— With files from Reuters and the Associated Press