WASHINGTON — Twenty-two more US House lawmakers are calling on President Barack Obama to adopt a policy of no-first-use of nuclear weapons, part of a tide of Democratic lawmakers pushing for restraint on atomic arms as the sun sets on the current administration.

With relations between Washington and Moscow historically tense and unpredictable this week, the lawmakers in a letter to Obama on Thursday expressed worry over the two nations' launch-under-attack postures and "the risk of catastrophic miscalculation and full-scale nuclear war."

"As you know, were the United States to exercise its contingency plans to use nuclear weapons first in a conflict against a nuclear-armed adversary, a full-scale nuclear exchange could ensue, killing thousands of civilians," the letter reads. "For the security and safety of the world, military options that can spiral towards mutually assured destruction should not be on the table."

Thursday's letter was led by Rep. Barbara Lee, D-Calif., the Peace and Security Task Force chair for the Congressional Progressive Caucus. Another signatory was Rep. Keith Ellison, D-Minn. Ellison is the caucus' co-chair and his party's chief deputy whip in the House.

A no-first-use policy would minimize the need for "first strike" weapons, they argue in the letter, including the next-generation nuclear-armed cruise missile and intercontinental ballistic missiles, "which could generate significant cost savings and lead other nuclear-armed states to make similar calculations."

President Obama considered the reduction of the role of nuclear weapons part of his legacy and was earlier in the year reported to be considering a no-first-use policy declaration, but the New York Times reported last month that he is likely to abandon the proposal. Arms-reduction advocates have argued the declaration would be an important step as the cost of the administration's nuclear modernization plans threatens to reach $1 trillion.

Defense Secretary Ash Carter and Secretary of State John Kerry had expressed concern that new moves by Russia and China, from the Baltic to the South China Sea, made it the wrong time to issue the declaration, the Times reported, citing senior aides in the Defense and State departments. Secretary of Energy Ernie Moniz, whose department oversees the nuclear arsenal, objected too, administration officials reportedly confirmed.

On Thursday, the Russian foreign ministry accused the Obama administration of destroying relations with Moscow in the run-up to the US presidential election next month, according to published reports. Flash-points between the two include an allegedly-Russian hacking campaign targeting US elections, dueling military operations in Syria, and Russia's demands that the US scale back military operations in the Baltics.

As Obama reviewed a potential disarmament agenda during his last months in office, there had been a flurry of activity on Capitol Hill to try to influence the internal debate. The Oct. 13 letter was the latest indication, as lawmakers with opposing views on nuclear modernization have fired off dueling letters.

"There is a sentiment that the president is in this place that his advisors aren't," said a Democratic aide working on the issue. "Some members wanted to make the point that there is support for this policy on Capitol Hill."

On July 20, five key House Democrats who want to scale back standing nuclear modernization plans — including HASC ranking member Adam Smith, of Washington — backed a no-first-use policy declaration and eliminating the launch-on-warning nuclear posture.

Another July 20 letter, from 10 Democratic senators, urged Obama to cancel development of the Long-Range Standoff cruise missile, which will replace the aging Air-Launched Cruise Missile program.

A mixed group of 14 senators signed a July 8 letter spearheaded by Sen. John Hoeven, R-N.D., that called on the administration to reaffirm its commitment to modernize the nation's nuclear triad. The signatories included the Senate Armed Services Committee's ranking member Jack Reed, D-R.I., and Tim Kaine, D-Va., the running mate of Democratic presidential candidate Hillary Clinton. 

Neither presidential candidate has made clear their position on no-first-use. During the presidential debate last month, Clinton gave a vague answer on the question of no-first-use, and Republican candidate Donald Trump gave a contradictory answer.

Email:   jgould@defensenews.com  

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Joe Gould was the senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry. He had previously served as Congress reporter.

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