The return to the U.S. policy of deterring North Korean aggression toward the South by threatening a devastating counterattack is working, a senior U.S. intelligence adviser said Thursday.
The comments came in the wake of a new report detailing “dramatic” construction underway at North Korea’s main rocket launch site, which North Korean leader Kim Jong Un vowed to close in 2018 amid his short-lived détente with then-President Donald Trump.
Speaking at an event at the Center for Strategic and International Studies, Sydney Seiler, the national intelligence officer for North Korea at the US National Intelligence Council, said that the return of US policies of “extended deterrence” to the north proved to be a success.
“The good news is that for now North Korea understands the overwhelming strength of the US-ROK alliance. It is fully aware of our commitment to defend the Republic of Korea,” Seiler said, adding that the Kim regime was also clearly annoyed by the growing US relations with regional powers Japan, Australia and India.
But Seiler said he was not concerned about renewed North Korean and Chinese propaganda decrying the return of US deterrence and growing US regional alliances across Asia. Instead, he said the fiery response to both “proves to me that they work.”
“China will continue to deploy rhetoric, North Korea will likely increase that rhetoric with a lot of tension, increasing demonstrations of force and training, etc., to try to deter us,” he said, but “the mere deployment of these capabilities is not itself will lead to some inevitable escalation about which we must be concerned.”
Construction of satellite launch
Seiler’s remarks came two days after CSIS issued a report detailed what it called “dramatic and ongoing” construction at the North’s main rocket launch site, the Sohae Satellite Launching Station, located near its northwestern border with China. Kim visited site in March and ordered officials to expand its capabilities.
The CSIS report said the expanded development appeared to be aimed at “supporting the long-term goal of launching larger and more capable spacecraft,” such as military reconnaissance satellites, although such capabilities were not currently in place.

“If all the announced modernization plans are completed and operational, it will provide North Korea with a comprehensive complex” of technology “usable by North Korea’s new intercontinental ballistic missile (ICBM) programs,” it said.
Resuming development of the facility, which Kim promised to shut down during his détente with Trump, has been a central plank in North Korea’s response to renewed US-led deterrence policies.
Not everyone is as happy about the Kim regime’s likely response to the return of the “deterrence” policy favored by the administrations that have taken office in Washington and Seoul over the past two years.
Speaking at the same CSIS event as Seiler, Sue Mi Terry, the director of the Asia program at the Wilson Center, said she was not sure Pyongyang would necessarily always back away from the conflict.
“I’m not going to say Syd isn’t worried — of course he is — but I think I’m more worried,” Terry said.
She singled out Pyongyang’s recent launch of short-range missiles that simulated a tactical nuclear attack on the South and its new law describing when it would use nuclear weapons in a conflict, which she described as “lowering the threshold for nuclear use.”
“North Korea has demonstrated its ability to deploy tactical nuclear weapons, [and] they’ve been very focused on tactical nukes,” Terry warned. “We don’t know what Kim Jong Un is thinking. I won’t be averse to that.”