A FORMER US ambassador has warned the US could lapse into a new nuclear arms race with Russia after details of a draft Nuclear Posture Review was leaked.

The Pentagon’s draft review, if approved by US President Donald Trump, would actually expand the conditions under which America would use nuclear weapons, according to former US Ambassador to Germany, Richard Burt, a former US chief negotiator of the Strategic Arms Reduction Treaty.

In an opinion piece for National Interest, Mr Burt and co-author Jon Wolfshal, the former senior director for arms control at the National Security Council, said the Nuclear Posture Review (NPR) sought to add two new nuclear weapons to the American arsenal and would “significantly lower the threshold for nuclear use”.

This includes a new type of low-yield weapon, also known as “tactical” nukes that could be as destructive as the bombs dropped on Hiroshima and Nagasaki at the end of World War II.

Policymakers worry that regular, large-yield weapons are essentially too big to ever be detonated, as their use would likely result in large-scale retaliation from an adversary and cause too much damage.

The Pentagon argues that by having more, smaller nukes it will counter adversaries’ “mistaken confidence” that the United States would not respond to another country using its own low-yield bomb.

“Expanding flexible US nuclear options now, to include low-yield options, is important for the preservation of credible deterrence against regional aggression,” the document states.

While Mr Burt believes the deterrence aspect of the nuclear program is important, especially in sending a strong message to countries like Russia and North Korea that any decision to use nuclear weapons would be met with severe consequences, he believes the review does not focus enough on trying to reduce the number of nuclear weapons. Indeed, it ignores how important this is in reducing nuclear risks.

“By dismissing and seeing arms control mainly as an unwanted constraint on American freedom of action, the NPR sadly undervalues the role that arms control and engagement with Russia has and can again play in reducing nuclear risks and restoring both strategic and crisis stability with America’s main nuclear rival,” the article states.

Mr Burt believes the review falls “woefully short” in setting out a way of ending the “action-reaction” cycle the US is increasingly engaged in with Russia.

“Russia is now in the process of rebuilding much of the Soviet Union’s strategic nuclear arsenal, including mobile, intercontinental-range ballistic missiles and a new fleet of missile-armed submarines,” the article states.

“The United States is in an early stage of a trillion-dollar plus modernisation program of its own, including new submarine and land-based missiles and a new stealth bomber armed with a new stealthy, long-range cruise missile.”

Instead of seeking reduce the number of weapons, the Pentagon’s leaked review hints that the US modernisation program ordered by former president Barack Obama, could even be increased beyond submarine launched warheads and sea-launched cruise missiles.

“This ongoing arms competition is fuelling a new dangerous dynamic that could threaten the security of Russia and the United States,” the article states.

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“As each side deploys new systems, they both perceive the worst in the military capabilities and intentions of the other and each seeks, through additional deployments, to restore the overall balance. The result is an action-reaction cycle of new nuclear deployments.

“It was a similar dynamic from the 1960s through the 1980s that led the two sides to deploy tens of thousands of nuclear weapons, leaving them both vulnerable to the ever-present threats of nuclear use by accident or through miscalculation.”

Mr Burt points out that the Pentagon’s review doesn’t give enough thought to how “engagement, diplomacy and verification” can be used to “reverse the dangerous trends in US-Russian nuclear matters”.

In the past, the US and Russia have agreed to limit nuclear weapons through agreements and treaties. This includes the 2010 New START agreement that limits each country to 1550 nuclear warheads.

But another important agreement is now on “life support” with both the US and Russia appearing to hint they may be willing to walk away from the 1987 Intermediate-Range Nuclear Forces Treaty, which bans both sides from deploying medium range ground-launched nuclear missiles.

This is particularly dangerous because it would undermine “crisis stability” as these types of missiles are designed to travel over shorter distances and would shorten the time leaders have to make decisions in case of a nuclear strike.

“The INF Treaty was negotiated because neither (former US president) Ronald Reagan nor (former Soviet Union leader) Mikhail Gorbachev felt secure, in the midst of a deep Soviet-American crisis, in having less than ten minutes to decide whether or not unleash their huge nuclear arsenals,” the article notes.

Thanks to the treaty, Europe has enjoyed 30 years of stability but this now at risk.

Russia is becoming increasingly suspicious of America’s missile-defence capabilities in Europe and it appears to be deploying a new generation of missiles.

In response, the review calls for the US to deploy a new sea-launched cruise missile, partly as a way of pushing Russia towards abiding by the treaty.

“Surprisingly, there is no discussion of more feasible and less dangerous ways to motivate Russia,” the article states.

This could include addressing Russia’s concerns about NATO’s missile defence in Europe through better transparency and verification to show it’s not able to launch weapons banned by the treaty.

Mr Burt noted that it has been seven years since the US and Russian negotiators came together to agree on the New START agreement.

“This is the longest hiatus since bilateral arms control began after the Cuban missile crisis,” the article stated.

He said a new round of talks should encourage both parties to abide by the treaty on intermediate-range nuclear missiles, and extend New START, which is due to expire in 2021.

“The emerging US-Russian nuclear relationship raises some complex problems, with few simple solutions,” he said.

“But experience has shown that at least one solution lies with direct, Russian-American engagement and seeking to negotiate arms control agreements.”

‘NUCLEAR WAR-FIGHTING’

As president-elect in December 2016, Donald Trump called for the United States to “greatly strengthen and expand” its nuclear capabilities — and within days of entering office he called for a new nuclear policy.

The nuclear review states that the development of new, lower-yield nuclear weapons is not intended to enable “nuclear war-fighting” that would see the US military using the weapons on the battlefield.

The Pentagon declined to comment on the policy review, saying it remained “pre-decisional” and not approved by Trump. The final version is due for release on February 2.

The document also states that Russia is upgrading its nuclear “triad” of air, sea and land-based missiles to include a new “hypersonic glide vehicle” and a new intercontinental, nuclear-armed, undersea autonomous torpedo.

The New York Times reported Wednesday that the policy review also outlines changes to the threshold at which America could respond with nuclear weapons — including a massive cyber attack.

The document states that the United States would only consider using nuclear weapons in “extreme circumstances.” These include “attacks on the US, allied, or partner civilian population or infrastructure, their command and control, or warning and attack assessment capabilities,” the document states.

Blechman said this goes against the spirit of the 1968 global non-proliferation treaty aimed at curtailing the spread of nuclear weapons.

“It would encourage those in many other countries who argue that nuclear weapons are essential to security,” he said.

The nuclear review states its commitment to the non-proliferation treaty “remains strong.” But, it goes on, “the current environment makes further progress toward nuclear arms reductions in the near term extremely challenging.”

Michaela Dodge, a senior policy analyst at the conservative US Heritage Foundation think tank, disputed critics’ contention that the new policy could lead to more conflict, or that it would break the spirit of the non-proliferation treaty.

“Additionally, a decision to use nuclear weapons would not be made haphazardly,” she told AFP.

The nuclear posture review “process is run by serious people with in-depth understanding of difficult nuclear weapons policy challenges.”