International security analysts have cast doubt on reports that the United States may be considering a preemptive military strike against North Korea, warning such action could have huge consequences on a key U.S. ally and upset a carefully managed balance of power between Kim Jong Un and the West.

NBC News, citing multiple senior intelligence officials, reported Thursday evening that the U.S. may launch military action against North Korea if it carried out suspected plans to conduct its sixth nuclear test in the coming days.

Several reports have speculated the North could do so after satellite imagery showed an unusual level of activity at the country’s Punggye-ri nuclear testing facility. And North Korea’s vice foreign minister told the Associated Press Friday that Pyongyang has no qualms about launching a preemptive strike if the U.S. displayed any “reckless” military aggression.

Moreover, Saturday marks the 105th birthday of North Korea’s founder Kim Il Sung, and the isolated nation often conducts grand military tests as a show of strength around major anniversaries.

But experts say ballistic missiles tests the North launched in recent months timed to meetings between President Donald Trump and the leaders of China and Japan, along with its propensity for grandiose promises of war, follow “seasonal” patterns.

Jonathan D. Pollack, the interim SK-Korea Foundation chair in Korea Studies at the Brookings Institution, notes the North often condemns military drills that the U.S. and South Korea conduct anually ― a 40-year-old tradition that involves more than 30,000 American troops. North Korea retaliated against the exercises, known as Foal Eagle, once again this year, with Kim personally overseeing the launch of four ballistic missiles in March.

“The consistent response of North Korea under those circumstances is to threaten the most dire of actions if the U.S. does anything: ‘If the aggressors bear to infringe on one inch of our sacred territory!” Pollack cited as an example. “It makes very bold copy, but it’s seasonal.”

This time, however, the Trump administration has shifted tack, threatening to upend years of diplomatic policy against the North that are often centered around economic sanctions and a hope that the hermit country’s prime ally, China, will keep its neighbor in check.

But experts say such a move would result in “enormous consequences.”

Credit: Damir Sagolj / Reuters Analysts have warned North Korea may be planning its sixth nuclear test to coincide with the birthday of founder Kim Il Sung, the grandfather of current North Korean leader Kim Jong Un.

South Korea’s capital and largest city, Seoul, lies less than 35 miles from the Demilitarized Zone, the heavily armed, de facto border between the two nations. Experts have long said simple geography provides one of the biggest deterrents for direct action against the North: The region around Seoul is home to more than 50 percent of South Korea’s population and within easy striking distance of the North’s vast non-nuclear arsenal.

Melissa Hanham, a senior research associate at the James Martin Center for Nonproliferation Studies, said no matter what happens with North Korea’s weapons of mass destruction, the country already has “enough conventional forces to deeply harm Seoul” and one of the largest standing militaries on the planet.

“North Korea has plenty of artillery,” Hanham said. “Regardless of whether a nuclear test is conducted, an ICBM launch is conducted, regardless of whether they’re able to produce a long-range warhead that sits on top of their missiles, Seoul is so close there is no way it would not suffer enormous consequences.”

No one denies that North Korea is expected to have the capacity to deliver a nuclear-armed ballistic missile capable of reaching U.S. soil. The country has succeeded in testing more powerful weapons in each of its five tests and is suspected of having the capacity to deliver a nuclear-armed ballistic missile across the Pacific within a decade.

But the Brookings Institution’s Pollack said the U.S. has been gaming out the impact of a direct military assault since the end of the Korean War. Every plan, he said, lands on the same result: “There’s just no good way to do this, period.”

“Every one of these exercises ends up concluding that the U.S. and South Korea would ‘win the war,’ but that the price of winning would be so extreme for South Korea,” Pollack said, noting Seoul is the world’s 11th largest economy and home to more than 25 million people.

“It’s a situation you’re kind of stuck with because there doesn’t seem to be an easy way, with any degree of confidence, that you could presume to take out all the nuclear weapons, wherever they are located, take out all of their capacity to inflict damage on South Korea,” he added. “You realize just how risky this strategy is.”

Credit: NurPhoto via Getty Images A North Korean solider and a South Korean soldier stand guard at the demilitarized zone.

In recent days, South Korea has sought to reassure its citizens that the U.S. won’t conduct military action without its consent. The New York Times reports growing anxiety within the country, currently without a leader after the impeachment of former President Park Geun-hye, has prompted officials to publicly reiterate the long-standing alliance between Seoul and Washington.

The Pentagon declined to elaborate on the NBC report, saying “for security reasons, we do not discuss future operations nor publicly speculate on possible scenarios.”

“Commanders are always considering a full range of options to protect against any contingencies,” Dana White, chief spokesperson for the office of the Secretary of Defense, said in a statement. “Our commitment to the defense of our allies, including the Republic of Korea and Japan, in the face of potential threats, remains steadfast.”

The Huffington Post has also reached out to the State Department for comment.

Pollack called allegations that the U.S. would consider a military strike “goofy” and said that such talk could ultimately “trigger exactly what no one would wish to see ... preemptive moves by the North Koreans against the South.”

The James Martin Center for Nonproliferation Studies’ Hanham echoed those concerns. With all the speculation, if the North doesn’t test a nuclear weapon after all, Kim will look “like a chicken,” she said. And for the North, “propaganda is so important to always look strong, to always look infallible ... he has to send a message back to his people that he’s completely in control.”

“The irony is, if this hadn’t leaked at all, maybe North Korea wouldn’t have tested,” said Hanham, who has been publicly critical of the leaks to NBC.

“We’ve seen from satellite imagery that conditions are good that they could test. But it’s possible that they would’ve let the reporters in Pyongyang watch a parade and leave. Now, with these leaks, there’s going to be an expectation that North Korea does something.”

Pollack noted it’s likely Trump is playing a grand game of brinkmanship with China, and the countries have been working to craft a diplomatic strategy to help head off the North’s nuclear ambitions. But despite Trump’s rhetoric, Pollack stressed military officials aren’t likely to make a rash decision with the risks so great.

“Whoever is doing the planning right now in the United States is applying very carefully the lessons drawn from the innumerable studies and assessments that have gone on literally for decades,” Pollack said. “I can only hope that [Trump’s] military advisors are giving him the prudent and sensible advice that any president needs. There are no good options. They do not exist.”

This article has been updated with comment from North Korea’s vice foreign minister.

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