South Korean President Yoon Suk Yeol and White House Indo-Pacific Coordinator Kurt Campbell met in Seoul Tuesday for the Nuclear Consultative Group's (NCG) inaugural meeting.
Cha said the aim of the meeting is for the U.S. to show South Korea a "look inside the nuclear box," and to garner confidence that the U.S. is committed to defending South Korea against North Korea with its nuclear capabilities.
The meeting comes almost three months after U.S. President Joe Biden and Yoon issued the Washington Declaration.
Under the Washington Declaration, the , but will instead increase the number of military weapons and vehicles it sends to the country temporarily.
China has voiced concerns that the NCG will potentially lead to an arms race and instability in the Korean peninsula.
But Cha said the U.S. is just being "proactive" rather than "provocative."
"China doesn't like anything that the United States does with its allies to make the alliance stronger … The Chinese will always frame this as being threatening to their interest because they would like to dismantle the U.S. alliance system," he said.
"If the U.S. alliance system were to break down in Asia, this would have huge ramifications not just in the security realm, but also in the economic and financial realm," Cha added.
Despite their different views, South Korea still strives for a good relationship with China, its most important economic partner.
South Korea wants a relationship that's based on mutual respect, which means "they don't want the Chinese dictating to them how it can manage its own sovereign security," Cha said.
