The United States and its allies have military options for confronting North Korea — including an all-out invasion, more limited air and missile strikes, cyberattacks or a covert effort to oust the regime of Kim Jong Un.
But those scenarios carry enormous risks, including the possibilities of loss of life, loose nukes falling into terrorists’ hands or the conflict spreading to a wider Asian war.
The military options, as unthinkable as they seem, are gaining heightened attention as President Donald Trump threatens to retaliate with "fire and fury" if the communist regime continues its saber-rattling, while North Korea threatens a missile strike on Guam. Trump doubled down on his incendiary rhetoric Thursday, telling reporters that "maybe it wasn’t tough enough."
“North Korea better get their act together, or they’re gonna be in trouble like few nations ever have been in trouble in this world,” he said.
Here are actions the U.S. could take against North Korea — and the potential risks.
The Korean War never officially ended after the armistice in 1953, and the United States has had serious contingency plans for resumed combat on the peninsula ever since. But even the 21st-century U.S. military would face a daunting fight if it invaded to unseat Kim’s government.
North Korea’s active-duty military consists of 1.2 million people with another 600,000 in the reserves, the Congressional Research Service reported last year. It also has military facilities spread throughout the countryside and a vast network of underground caves and bunkers where it stores weapons close to its neighbor South Korea. Those include large stockpiles of outlawed chemical weapons, such as nerve gas.
More than 25,000 U.S. forces remain stationed in South Korea, operating under the motto of being ready to "fight tonight." The United States Pacific Command, headquartered in Hawaii, also has at its disposal far more American military personnel, including a full 60 percent of the Navy.
But even with significant help from South Korea’s highly trained armed forces — upward of 600,000 people — a go-for-broke invasion would require massive numbers of U.S. ground and air forces, missile ships and reinforcements. And it would probably require pulling American troops away from other national security priorities, writes Mark Almond, director of Oxford University’s Crisis Research Institute.
An offensive attack by U.S. and South Korean forces could also provoke a response from China, which borders North Korea and fought alongside it in the Korean War, raising the prospect of a great-power confrontation.
Almond also warns that a pre-emptive attack could compel the North Koreans to unleash thousands of short-range artillery rounds and other firepower across the 38th parallel and into Seoul, South Korea’s capital and largest city, which lies just 35 miles from the fortified border, killing tens of thousands of civilians.
Such a war would be far from a cakewalk, Defense Secretary Jim Mattis and Gen. Joseph Dunford, chairman of the Joint Chiefs of Staff, warned lawmakers at a hearing in June.
"I don’t have any doubt in my mind, if we go to war with North Korea, that we will win the war," Dunford said, but added that "we will see casualties unlike anything we’ve seen in 60 or 70 years."
Other attempts at regime change
Secretary of State Rex Tillerson said last week that the U.S. does “not seek a regime change” in North Korea, but CIA Director Mike Pompeo seemed to suggest last month that ousting the Kim regime and separating it from its nuclear arsenal were at least on the table.
Options for taking out Kim’s government include ground raids by special operations forces or drone or conventional airstrikes targeting the leader. The U.S. could also support a government in exile to help facilitate a coup by disgruntled North Koreans.
But as the U.S. learned in Iraq and Libya, regime change is not as simple as installing a new leader and leaving. One danger is that the new government could be even more anti-American or provocative than Kim’s was.
Another concern: North Korea’s nuclear capabilities could fall into the wrong hands during the ensuing chaos. Reports say North Korea, which has a history of selling missile technology on the black market, could have as many as 60 nuclear weapons.
An attempted strike on Kim could also prompt North Korea to launch a barrage of missiles at the U.S. or its allies, experts say.
The U.S. could use its long-range bombers, aircraft carriers and cruise missiles to strike specific North Korean targets, such as missile launch sites or nuclear weapons plants. Then-President Bill Clinton considered that option in the 1990s.
But success would be even more difficult than it might have been back then. The North’s covert nuclear and missile programs have advanced, including a heavy reliance on mobile missile launchers that would be difficult to locate.
Because it would be exceedingly difficult for the U.S. to destroy all of North Korea’s assets, the regime could quickly retaliate against South Korea, home to about 200,000 Americans, said Jonathan Pollack, a senior fellow at the Brookings Institution.
“Unless someone believes you can somehow go in, take out everything that North Korea has — and everything is a whole lot — there is going to be major retaliation against the South and Americans will die,” he said.
Estimates of North Korea’s missile stockpile differ drastically. A Newsweek report estimates the country has between 20 and 120 missiles.
There is little doubt that South Korea would be in grave danger from even a limited military strike on the North. The results of a 2005 war game published in The Atlantic estimated that 100,000 people would die in the first days of conflict if North Korea attacked Seoul.
The United States and its allies could attack the North Korean missile and nuclear programs using their cyber warriors without ever launching a missile or stepping foot in the region.
The New York Times reported in March that the military was tasked with using cyber and electronic means to stop North Korean test launches in their opening seconds. While several test launches after that either exploded or veered off course, it’s unclear if those failed tests were a result of U.S. efforts or technological flaws.
Increasing cyber activities could be useful, but most experts agree it would be an incomplete solution.
Responding after North Korea strikes first
North Korea has threatened by the middle of August to launch four missiles into the waters off Guam, the U.S. territory that lies about 2,000 miles away. If it follows through, the U.S. would probably attempt to either destroy the missiles on the launch pad with combat aircraft or shoot them down with missile defense systems deployed to the region, said Steven Stashwick, an independent analyst on East Asia security.
The defensive options include the Army’s Terminal High Altitude Area Defense system and Navy ships equipped with the Aegis ballistic missile defense system.
But those carry risks too. If the U.S. strikes the launch pads, deaths of North Korean soldiers or destruction of the North’s property would risk escalating the conflict. Or the missile defenses could miss the incoming North Korean rockets, eroding the defenses’ credibility as a deterrent, Stashwick said.
The THAAD system in Alaska conducted a successful intercept test last month, but tests of the anti-missile system have faced criticisms as being too scripted and far less difficult than a real-world bolt from the blue.
And while THAAD can counter threats from short-, intermediate- and long-range ballistic missiles, it is not designed to destroy the type of intercontinental ballistic missile that the North Koreans have been testing. North Korea’s most recent tests show it has ICBMs that could reach the U.S. mainland, although its ability to hit the United States with a nuclear warhead is still unproven.
The U.S. has a separate network of missile interceptors in Alaska and California, called the Ground Based Strategic Deterrent, that is designed to defend the United States from an ICBM plunging from space at vast speeds. But that system is widely considered less reliable than the regional missile defenses.
It’s all the more reason why most experts say the U.S. has no choice to but to find a way to negotiate with the North Koreans.
"The objective of them ending their nuclear missile program is over," said former New Mexico Gov. Bill Richardson, a former U.S. ambassador to the United Nations and Energy secretary who has traveled to North Korea on several humanitarian missions. "The strategy should be containment — freezing and reducing their nuclear program and international inspections.
"The days where you are saying they have to end their nuclear program and then we will talk are over," he added. "That’s failed."