The U.S. Department of Defense has made deterring China’s invasion of Taiwan a military priority in a recent interim internal guidance memo, according to the Washington Post. This move is expected to change Washington’s security policy on the Korean Peninsula significantly. The traditional role of U.S. Forces Korea, which has long focused on deterring North Korea, could expand to include defending Taiwan and countering China—potentially increasing the burden on South Korea’s military readiness against North Korea.
Experts warn that the U.S. could demand higher defense cost-sharing for hosting American troops in Korea and call for a hike in Korea’s defense spending.
The Washington Post reported on March 29 that a secret Pentagon internal guidance memo, distributed throughout the Defense Department and signed by Defense Secretary Pete Hegseth, prioritizes “deterring China’s seizure of Taiwan” by assuming risk in Europe and other parts of the world. The memo indicates that U.S. allies in Europe, the Middle East, and East Asia will be pressured to spend more on defense so that they can take on greater responsibility in deterring threats from Russia, North Korea, and Iran.
Experts suggest the Pentagon has signaled a policy shift for South Korea through this memo. “The Trump administration has made it clear that, whether it is U.S. forces in Korea, Japan, or Australia, the ultimate target is China,” said Kim Sung-Han, former Director of the National Security of South Korea. ”If China invades Taiwan, the U.S. will inevitably intervene, and the Korean Peninsula will be swept up in the resulting storm.” This implies that the role of U.S. forces in Korea could be adjusted to include measures for deterring China.
A high-ranking military official noted that the current U.S. strategic framework separates Northeast Asia into two theaters of operations—the Korean Peninsula and the Taiwan Strait—but that may soon change. “The Pentagon may be considering integrating the two into a single Northeast Asia theater,” the official said.
“The U.S. believes China could gain the capability to invade and occupy Taiwan by 2027, and it wants to finalize alliance role adjustments by then,” said Park Won-gon, a professor at Ewha Womans University. “The role of the U.S. forces in Korea will be expanded to defending Taiwan, meaning South Korea will have to fend off North Korean threats on its own.” Some experts raised concerns that the U.S. could consider wartime operational control from the Commander of the ROK-U.S. Combined Forces Command to the South Korean military.
As Washington pivots toward confronting China, it is expected to scale back its direct involvement in Europe, the Middle East, and East Asia. Instead, responsibilities for countering Russia would shift to NATO, addressing Iran would fall to Israel and Saudi Arabia, and deterring North Korea would increasingly rely on South Korea and Japan. “President Trump strongly believes that the U.S. has been bearing an excessive burden on behalf of its allies,” said a diplomatic source.
Seoul is expected to face immediate pressure to increase defense cost sharing for U.S. troops stationed in Korea. During his presidential campaign last year, Trump labeled South Korea a “money machine” and said the long-time U.S. ally should pay $10 billion annually for defense costs—roughly ten times the 1.4 trillion won it contributed this year.
With a potential U.S. policy realignment on the horizon, experts say the government must prepare for these changes. “If the role of U.S. forces in Korea expands to include countering China, Korea’s deterrence posture against North Korea will inevitably weaken,” said former Deputy Defense Minister Shin Beom-chul. As a countermeasure, he suggested that South Korea could request the U.S. deploy tactical nuclear weapons to Guam. Another proposal under consideration is asking the U.S. to grant permission for South Korea to develop nuclear-powered submarines to bolster its deterrence against North Korea.
