Rubio and the North Korean nuclear test

Rubio blasts Obama after North Korean nuclear test

By Nick Gass and Hanna Trudo

Sen. Marco Rubio ripped into President Barack Obama late Tuesday night after North Korea claimed to have conducted the successful test of a hydrogen bomb.

"I have been warning throughout this campaign that North Korea is run by a lunatic who has been expanding his nuclear arsenal while President Obama has stood idly by," the Florida senator and Republican presidential candidate said in a statement.

“If this test is confirmed, it will be just the latest example of the failed Obama-Clinton foreign policy," he said. "Our enemies around the world are taking advantage of Obama's weakness. We need new leadership that will stand up to people like Kim Jong-un and ensure our country has the capabilities necessary to keep America safe."

Sen. Bernie Sanders on Wednesday morning called upon the U.S. to press China into forcing North Korea to abide by international norms.

"China is equally concerned about what North Korea is doing. North Korea is a paranoid, isolated nation," the independent Vermont senator and Democratic presidential candidate told ABC's "Good Morning America." "When you have a hydrogen bomb, if that’s true, you are a threat to China as well.”

The White House said it was "aware of seismic activity on the Korean Peninsula," but declined to immediately confirm the nuclear test. The United States is "monitoring and continuing to assess the situation in close coordination with our regional partners," National Security Council spokesman Ned Price said in a statement, "and will respond appropriately to any and all North Korean provocations."

The United Nations Security Council on Wednesday called an emergency session following those reports.

In a separate statement, NATO's secretary general called on the North Korean regime to abandon its nuclear weapons and comply with the international community.

"The nuclear weapons test announced by North Korea undermines regional and international security, and is in clear breach of UN Security Council resolutions," NATO Secretary General Jens Stoltenberg said. "I condemn the continued development by North Korea of nuclear weapons and ballistic missile programs and its inflammatory and threatening rhetoric. I call on North Korea to fully respect its international obligations and commitments. North Korea should abandon nuclear weapons and existing nuclear and ballistic missile programs in a complete, verifiable and irreversible manner, and engage in credible and authentic talks on denuclearization."

Yukiya Amano, director general of the International Atomic Energy Agency, said in a statement Wednesday that, if its claims are true, North Korea is violating U.N. Security Council resolutions — which he added “is deeply regrettable.”

“I strongly urge the [Democratic People’s Republic of Korea] to implement fully all relevant resolutions of the U.N. Security Council and the IAEA,” he said. “The IAEA remains ready to contribute to the peaceful resolution of the DPRK nuclear issue by resuming its nuclear verification activities in the DPRK once a political agreement is reached among the countries concerned.”

In December, the White House expressed doubt that North Korea had the capability to build a hydrogen bomb, which in theory would have vastly more explosive power than the Pyongyang regime's existing capabilities.

"At this point, the information that we have access to calls into serious question those claims, but we take very seriously the risk and the threat that is posed by the North Korean regime in their ambitions to develop a nuclear weapon," White House press secretary Josh Earnest told reporters at the time.

Nuclear proliferation experts have similarly discounted Pyongyang's claims, but have speculated that North Korea might be able to boost its "explosive yield" through other means — including a so-called fusion fuel such as tritium.

“Tritium would enable nuclear weapons designs that could have a greater explosive yield than weapons made from only plutonium or weapon-grade uranium,” nuclear experts David Albright and Serena Kelleher-Vergantini of Washington's Institute for Science and International Security wrote in September. “Whether North Korea can make nuclear weapons using tritium is unknown although we believe that it remains a technical problem North Korea still needs to solve.”

"Building a staged thermonuclear weapon—one in which the radiation from a fission primary compresses a secondary stage of thermonuclear fuel—would seem to be a bit of a stretch for the North Koreans," Jeffrey Lewis of the James Martin Center for Nonproliferation Studies wrote in December.

But, he noted, "while a staged thermonuclear weapon is likely more than North Korea can, at the moment, achieve technically, it is a mistake to rule out the aspiration by Pyongyang. An H-bomb might not conveniently fit our perception of North Korea, but perhaps that is Kim’s point."