A U.S. nuclear-powered aircraft carrier arrived in the South Korean port city of Busan on Tuesday, the third such visit just this year in what experts described as a bid to demonstrate Washington’s willingness to defend the ROK against North Korean threats.

The ROK navy connected the arrival of the USS Carl Vinson to the first meeting of the U.S.-South Korea Nuclear Consultative Group (NCG) in July and the 55th U.S.-South Korea Security Consultative Meeting (SCM) held last week.

The allies formed the NCG earlier this year as a forum for discussing the use of U.S. nuclear weapons in South