Submarine-launched ballistic missiles are paraded across Kim Il Sung Square in Pyongyang, North Korea. (Wong Maye-E/AP)
About the authors
Catherine Dill is a senior research associate at the Middlebury Institute of International Studies in Monterey.
Joshua Pollack is a senior research associate at the Middlebury Institute of International Studies in Monterey, and the editor of the Nonproliferation Review.

North Korea’s test launches have brought the possibility of a nuclear strike firmly back into the American consciousness. A recent survey by the Chicago Council on Global Affairs found that three-quarters of Americans now consider North Korea to be a “critical threat” to the United States. U.S. intelligence analysts believe that North Korea may start deploying intercontinental ballistic missiles (ICBMs) as soon as next year. And they think North Korea can fit nuclear warheads onto those missiles. How easy is it to detonate a nuclear weapon on foreign soil? Here are five myths about missiles, threats and deterrence.

Myth No. 1
For deterrence, countries must display functional weapons.

“North Korean missiles may reach US, but lack effective re-entry,” one Fox News article supplied soothingly this month. “Serious questions remain around North Korea’s ability to build vehicles to reenter the planet’s atmosphere through tremendous pressure and friction,” a Business Insider story explained . It sounds as if North Korea can’t be a threat if it hasn’t launched a projectile across the ocean.

But countries have never held their enemies to this standard. Early in the Cold War, nations tested nuclear weapons in a variety of settings, including underwater and underground. The United States and the Soviet Union also launched nuclear weapons on missiles, detonating them in the upper atmosphere or in space. At least once, on Feb. 2, 1956 , the Soviets launched a nuclear weapon into space on a medium-range missile, allowing it to reenter and detonate inside the atmosphere. On May 6, 1962 , the United States did the same from a submarine.

In 1963, the United States, the Soviet Union and Britain signed the Limited Test Ban Treaty, moving all testing underground. Since then, the only nuclear missile test involving reentry was conducted by China on Oct. 27, 1966, with a medium-range missile. No country has ever attempted to demonstrate an ICBM in this fashion. Still, no one questions whether America, Britain, China, France or Russia have working nuclear missiles.

Myth No. 2
The U.S. could destroy an enemy’s arsenal on the ground.

In his game plan for war with North Korea, the New York Post’s Ralph Peters — a retired Army lieutenant colonel — placed the following high on his to-do list: “We’d go for the missile and nuke infrastructure,” including scientists, technicians and the bombs themselves. Likewise, Time told readers in 2015 that, should Iran develop the ability to use nuclear weapons, they could “look for the Air Force’s Massive Ordnance Penetrator to get the assignment to try to destroy that capability.”

But that might not be so simple. Little is known in detail about the current ability of the United States to seek out and destroy mobile missiles before they launch, but it has been a notoriously tough problem in the past. During the 1991 Gulf War, the U.S. military flew thousands of missions against Iraq’s Scud missiles but could not confirm a single kill .

Capabilities have improved, but by all indications, the job remains difficult. Just last month, Gen. Paul Selva , the vice chairman of the Joint Chiefs of Staff, told senators that the U.S. intelligence community cannot reliably track the deployment of North Korean missiles in the field. He noted that “Kim Jong Un and his forces are very good at camouflage, concealment and deception.”

Myth No. 3
The U.S. could shoot down enemy warheads in flight.

After North Korea’s latest ICBM test, Gen. Lori Robinson, who leads U.S. Northern Command and the North American Aerospace Defense Command (NORAD), expressed “unwavering . . . confidence that we can fully defend the United States against this ballistic missile threat.” After a recent test of American anti-ICBM procedures, Vice Adm. Jim Syring, the director of the Missile Defence Agency, said the test “demonstrates that we have a capable, credible deterrent against a very real threat.” That makes it sound like the United States would have no problem knocking North Korean nuclear warheads out of the sky if it were ever necessary.

Any attempt to stop an ICBM attack would depend on the Ground-Based Midcourse Defense (GMD) system, which the United States has built and deployed for that purpose. It successfully intercepted an ICBM-class target for the first time in a test in May. Unfortunately, its overall track record is less impressive. The Pentagon’s Operational Test and Evaluation office slammed GMD in its annual report for 2016 , pointing to frequent failures, insufficient testing and inadequate radar support. A detailed report from the Union of Concerned Scientists describes these results as an outcome of more than a decade of relaxed oversight. It will be a very long time before the shortcomings of the program can be corrected — if ever.

Myth No. 4
Deterrence can’t work against a country like North Korea.

National security adviser H.R. McMaster recently told ABC News that “classical deterrence theory” doesn’t apply to a regime like North Korea’s, one that “engages in unspeakable brutality against its own people.” Likewise, former assistant defense secretary Mary Beth Long didn’t seem to have high hopes for deterrence while speaking on a recent panel: “We tried to deter North Korea from having a nuclear program. That didn’t work. We tried to deter North Korea from having a nuclear program outside the NPT [Non-Proliferation Treaty]. That didn’t work. We tried to deter North Korea from hiding. That didn’t work.”

Yet nuclear deterrence has held so far: Nuclear weapons have not been used in war since 1945, despite being in the arsenals of nine countries (with sometimes erratic leaders) today. Dogfights between the American and Soviet air forces during the Korean War, border clashes between the U.S.S.R. and China in 1969, and a small-scale war between India and Pakistan in 1999 did not trigger mushroom clouds.

North Korea itself appears to have been, at least thus far, held back by deterrence. On June 25, 1950, the North Koreans marched south in an attempt to unify the Korean Peninsula by force. The invasion failed, leading to a grinding, three-year war, untold deaths and the destruction of North Korea’s infrastructure from the air. North Korea has never given up on its ambitions for reunification, but it has not tried to invade a second time.

Deterrence may fail eventually, but so far, it’s working.

Myth No. 5
First-generation nuclear weapons are hard to make.

That enriching uranium is notoriously hard supposedly keeps a bomb boom at bay. “Manufacturing high-quality fuel” — plutonium or highly enriched uranium — “is the most difficult part of any nuclear program,” author William Langewiesche noted in the Atlantic in 2006. “The big problem in making a nuclear bomb is that you need enriched uranium,” Gizmodo agreed in 2012 , “and that’s actually a real pain in the a-- to make.”

But technology is no longer a serious barrier to making nuclear bombs. In a forthcoming article in the Nonproliferation Review, “Opening a Proliferation Pandora’s Box,” MIT professor R. Scott Kemp describes how knowledge spread around the world about a new technique for uranium enrichment: a relatively simple and inexpensive gas centrifuge. A laboratory in the Soviet Union completed the invention in the mid-1950s, relying on the skills of German and Austrian prisoners of war. After the prisoners went home, some of them set about re-creating it, first in West Germany and then in the United States.

Word got around. Unclassified reports from the American project circulated, becoming a “recipe book” for simple centrifuges. In the following years, countries large and small, wealthy and poor — Australia, Brazil, Britain, China, France, India, Italy, Israel, the Netherlands and Japan — all produced versions of the Soviet technology for enriching uranium.

outlook@washpost.com

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