The U.S. armed forces appear to have been sending their strategic weapons to South Korea in greater secrecy, a move that would maximize fear for North Korea.
A military official said on condition of anonymity, Sunday, that increasing the dispatch of weapons in secret reflects the Donald Trump administration's shifting toward offensive measures in dealing with the North's evolving threats as U.S. Secretary of State Rex Tillerson vowed to explore all options including military action.
"Surprise dispatch of strategic weapons is effective in maximizing fear in the North as it sends a message that such weapons can be mobilized any time in case of a contingency," the official said.
In the latest series of mobilizations, it was belatedly known that Washington had sent several F-35B stealth fighters, deployed to the U.S. Forces Japan, to the Korean Peninsula last week.
During its sortie in support of joint training between South Korean and U.S. marines as part of the allies' annual Foal Eagle exercises, the fifth-generation fighter jets conducted a simulation-based bombing drill on a shooting range in Gangwon Province, a source said, adding that the drill was aimed at striking virtual targets in North Korea.
The visit was reportedly made from March 20 to 23, but it was known to the media only on Saturday when U.S. Forces Korea (USFK) Commander Gen. Vincent K. Brooks said the sortie reflects Washington's commitment to a robust alliance with Seoul.
"The deployment of the most advanced aircraft the U.S. Marine Corps has in its inventory to Korea is yet another example of how dedicated the United States is to supporting the ROK-U.S. Alliance," he said in a statement. "The training within the Korea Marine Exercise Program helps ensure our readiness and is critical for our alliance as we maintain security and stability on the Korean Peninsula."
It was also belatedly known that the U.S. Navy's USS Columbus, a fast-attack, nuclear-powered submarine, was participating in the joint drill that began March 19 in the nearby sea of South Korea.
Earlier, the U.S. also secretly sent two B-1B strategic bombers, deployed to Andersen Air Force Base on Guam, to the vicinity of South Korea, March 15.
Washington gave no advance notice to the South Korean media. The dispatch was known the following day after North Korea claimed, through its Korea Central News Agency (KCNA), that the B-1B Lancer bombers flew over a firing range of South Korea for about an hour on a drill aimed at making preemptive strikes at major targets of the North. It was believed that Pyongyang detected the flight of the bombers using its radars and accumulating information.
At the time, the USFK did not confirm the sortie, only saying, "We do not discuss operational matters."
In response to the allies' recent drills, North Korea threatened a preemptive strike.
The North Korean People's Army issued a statement, Sunday, saying that it is ready to fend off any attempts by enemy commandos to attack its leader, citing that U.S. commandos, including Navy SEAL Team Six and Delta Force, took part in the annual drills with South Korea.
Meanwhile, 38 North, the U.S.-based North Korea monitoring website, said that another indication that Pyongyang may be preparing for its sixth nuclear test has been detected, citing satellite imagery showing several vehicles or trailers at the entrance to the Punggye-ri nuclear test site.
"If these vehicles are related to test preparations, they could be involved in the installation of instrumentation or even a nuclear device," Joseph S. Bermudez Jr. and Jack Liu said in an article posted on the website.
However, the evidence is not definitive, therefore, they may be there for other purposes as well, they said.