North Korea carried out its most powerful nuclear test to date on Sunday, claiming to have developed an advanced hydrogen bomb that could sit atop an intercontinental ballistic missile.
The bomb used in the country’s sixth-ever nuclear test sent tremors across the region that were 10 times more powerful than Pyongyang’s previous test a year ago, Japanese officials said.
While the size of the bomb has not been independently verified, if true, the pariah state is a step closer to being able to fire a nuclear warhead to the US mainland, as it has repeatedly threatened to do.
Pyongyang has ratcheted up its ballistic missile testing this year and engaged in an exchange of threats with US President Donald Trump. It has developed projectiles that it says could reach the US mainland, and some experts say that’s likely true.
International outcry
US Ambassador to the United Nations Nikki Haley joined her counterparts from Japan, France, the United Kingdom and South Korea in requesting an emergency UN Security Council meeting on North Korea. It will be held Monday at 10 a.m. ET.
The request came after UN Secretary-General António Guterres also condemned the test, calling it “profoundly destabilizing for regional security.”
Sunday’s nuclear test is the first since Trump took office, and he condemned the test in a series of tweets, calling North Korea’s actions “hostile and dangerous to the United States.”
“North Korea is a rogue nation which has become a great threat and embarrassment to China, which is trying to help but with little success.”
“South Korea is finding, as I have told them, that their talk of appeasement with North Korea will not work, they only understand one thing!”
When asked by a reporter Sunday whether he would attack North Korea, Trump responded: “We’ll see.”
Trump later tweeted that he would meet with White House chief of staff, Gen. John Kelly, Defense Secretary James Mattis and other military leaders.
“The United States is considering, in addition to other options, stopping all trade with any country doing business with North Korea,” he said in another tweet.
A text message to reporters from South Korean President Moon Jae-in’s office said the republic was working with the international community to “ensure maximum sanctions and pressures against North Korea’s continued provocations.” It added that the US and South Korea “agree on using sanctions and pressures to have North Korea come to the table for talks.”
The text message concluded, “Korea is a country that has experienced war. … We can’t let this experience be repeated again on this land. We will pursue the denuclearization of the Korean peninsula through peace with our allies.”
Japanese Prime Minister Shinzo Abe said he spoke with Trump and Russian President Vladimir Putin on Sunday about North Korea’s “reckless act.” Abe said the US and Japan “stand together 100 percent,” and he plans to meet with Putin in Vladivostok, Russia, next week, and the two “have completely agreed to have a close coordination,” Abe told reporters.
Abe demanded “unprecedented strong pressure” on North Korea and said stopping North Korea’s hostile actions “depends on the solidarity and coordination with the international community.”
8 times the power of Hiroshima bomb
Sunday’s test came hours after North Korea released images of leader Kim Jong Un inspecting what it said was a hydrogen bomb ready to to top an ICBM, which the country would need to deliver a nuclear warhead to far-away locations.
State news anchor Ri Chun Hee hailed the test as a “perfect success” and the final step in attaining a “state nuclear force.”
The device was more than eight times more powerful than the nuclear bomb dropped on Hiroshima in 1945, according to NORSAR, a Norway-based group that monitors nuclear tests.
Based on the tremors that followed the test, NORSAR estimated it had an explosive yield of 120 kilotons. Hiroshima’s had 15 kilotons.
But South Korean officials gave a more modest estimation, saying that Sunday’s bomb had a yield of 50 kilotons.
Whatever the explosive yield, the device was undoubtedly powerful, and the test offers the first hint that North Korea could be more developed in its nuclear program than previously thought.
The country has for years worked on nuclear miniaturization so that it can create a warhead small and light enough to be fired over long distances.
Pressure on Trump and China
In a high-level national security meeting, South Korean President Moon Jae-in called the test “an absurd strategic mistake” that would lead to the international community further isolating Pyongyang.
But existing sanctions designed to isolate the country have in many ways failed. The Kim regime has developed its weapons and nuclear program despite the measures that have crippled the economy and exacerbated periods of mass starvation.
The White House will be under global pressure to deliver a coherent response to North Korea. It has been accused of sending mixed messages on the issue and lacking a clear strategy.
Trump’s administration is now pursuing what it calls a strategy of “peaceful pressure” to get North Korea to bring its nuclear weapons program to the negotiating table.
But the President’s regular tweets on the issue are at odds with this approach and suggest he is uninterested in dialogue.
Treasury Secretary Steven Mnuchin said Sunday he was drafting tough, new economic sanctions against North Korea, echoing the President’s stance, saying “this isn’t the time for just talk.”
Asked whether the nuclear test puts the US closer to military action, Mnuchin said that officials would look at all options.Â
“We are not going to broadcast our actions.”
China is also under pressure to do more to deter North Korea’s provocations as its most powerful ally and patron. Beijing condemned the test Sunday.
“We strongly urge (the) North Korea side to face up to the firm will of the international community on the denuclearization of the peninsula, abide by relevant resolutions of the UN Security Council, stop taking wrong actions that exacerbate the situation and are not in its own interest, and return to the track of resolving the issue through dialogue,” the Chinese Foreign Ministry said in a statement.
Continued provocation
Tensions between North Korea and the international community flared last week, when Pyongyang flew a ballistic missile for the first time over Japan. The US and its allies responded by sending fighter jets and bombers over the Korean Peninsula in a “show of force” operation.
Analysts have said for months that another nuclear test was likely on the way, with satellite imagery revealing that a new tunnel had been dug earlier this year.
“For months North Korea refrained from conducting a nuclear test and from launching missiles over Japan” said David Wright, the co-director of the Union of Concerned Scientists Global Security Program.
“It now seems to have decided to end that restraint.”
Can North Korea deliver a nuclear warhead?
Experts say it is nearly impossible to verify with certainty Pyongyang’s claim that it detonated a hydrogen bomb, which is also known as a thermonuclear weapon, or whether it can be used successfully on a missile.
Thermonuclear weapons typically use a fission explosion to create a fusion reaction, which is far more powerful than a fission reaction.
Sunday’s test comes almost one year after Pyongyang’s fifth nuclear test last September, which triggered a 5.3-magnitude seismological event. That took place on September 9, the country’s Foundation Day holiday.
North Korea claimed it set off a thermonuclear weapon during that test, but experts said the data showed it was more likely a boosted fission weapon.
