As North Korea’s nuclear program advances, the United States has sent repeatedly signaled it can track Pyongyang’s delivery systems, and thus destroy them in a preemptive strike.
This began with North Korea’s first test of an intercontinental ballistic missile (ICBM) on July 4. In the aftermath of the test, U.S. officials began telling reporters that it had observed North Korea preparing the launch. One example came from the Diplomat ’s Ankit Panda, a former colleague of mine who consistently does some of the best reporting on North Korea’s missile program. Tucked away in a larger article that cited a U.S. government source, Panda revealed that “the United States observed the missile on the launch pad near Pukchang Airport for about 70 minutes prior to its firing.” The day after the July 4 test, Fox News’ Jennifer Griffin also reported that “US official tells us the US watched the North Koreans prepare for this launch in advance. They saw the missile being fueled w/ liquid fuel.”
This pattern resumed in the run-up to North Korea’s second ICBM test on July 28, when American officials began leaking to multiple news outlets that U.S. intelligence was picking up indications of another ICBM test. These leaks began as early as July 19 and intensified over the next week. By the week of the test, U.S. officials were predicting that a test would “probably” come on July 27, the anniversary of the signing of the armistice that ended active fighting in the Korean War. One U.S. government source told Ankit Panda that “U.S. military intelligence has spotted a Hwasong-14 transporter-erector and firing-table transporter in Kusong,” in North Korea’s North Pyongan province.
Perhaps irked by the reports that U.S. officials had observed the first test, Pyongyang ended up conducted the second ICBM test from Mupyong-ni in northern Chagang Province, a mountainous region close to the Chinese border. It also conducted the test at night when, as Jeffrey Lewis notes , many U.S. satellites would not have been able to observe it.
The United States was not fooled, according to a government source once again speaking to Ankit Panda. Shortly after the launch, Panda reported , that—according to his source—the United States had been watching the site “for weeks and saw some of the preparations in the 24 hours preceding launch.” Panda went on to write: “the source added that confidence about an imminent launch on July 28 was high by about ‘four hours prior to launch.’ This assessment was also partly based on North Korea’s set-up of a VIP viewing area near the launch site for Kim Jong-un and other senior regime officials.”
Nor has the United States signaling been limited to North Korea’s ground-based missile forces. The United States has also been signaling that it can track Pyongyang's submarines, which has traditionally been the most survivable leg of a nuclear triad. Not surprisingly, then, North Korea has also been trying to build a submarine-launched ballistic missile force. But U.S. officials are now seeking to convey to Pyongyang that even those wouldn’t be safe from American intelligence. A defense official told CNN this week that the U.S. military has observed “highly unusual and unprecedented levels” of North Korean submarine activity. Specifically, the official said the U.S. has detected three ejection tests this month, and four of these so-called cold-launch tests this year. While these tests were conducted on land in a shipyard, the U.S. official went on to reveal that “a North Korean Sang-O submarine was operating in the Yellow Sea and the length of its deployment was notable. Two Romeo submarines were detected in the waters off Japan—each one operating in the area for about a week.”
All told, this is a concerted effort by the United States to signal that it can track North Korea’s delivery systems in real time. This is important because this capability would be necessary were the United States to decide to conduct a first strike to destroy Pyongyang’s nuclear weapons on the ground, perhaps preemptively if North Korea was getting ready to use them. That U.S. officials are signalling this publicly is undoubtedly meant to both intimidate North Korean leaders as well as reassure allies like South Korea of America’s commitment to their security now that Pyongyang has acquired (or will soon acquire) the ability to target U.S. cities with nuclear weapons.
America appears to be succeeding on the former front, as the deception North Korea used in conducting its second ICBM test suggests that Pyongyang is concerned about the survivability of its nuclear arsenal. This is a problem for virtually every nuclear power, especially during the early years after they first build the bomb. America panicked after Albert Wohlstetter demonstrated how vulnerable Strategic Air Command bases in Europe were to a Soviet first strike. Similarly, Jeffrey Goldberg and Marc Ambinder have reported that Pakistan regularly moves its nuclear weapons around using civilian, nonarmored vehicles driving on regular roads to escape detection. North Korea is especially vulnerable right now because it has a small number of warheads and many of its missiles—including the ICBM—are liquid fueled, which requires them to be fueled shortly before launch.