The U.S. and the ROK Agree to Hold Exercise to Plan Response to Use of Nuclear Weapons By North Korea
Considering the nuclear threats the Kim regime has continued to make against South Korea it makes sense to plan for how to respond to their use:

South Korea and the United States plan to stage a combined military exercise next month under the scenario of use of a nuclear weapon by North Korea, Seoul’s defense ministry said Wednesday in its report to President Yoon Suk Yeol on major policy tasks this year.
Among other plans are holding a 11-day springtime South Korea-U.S. exercise without a break, conducting a final test of a homegrown solid-propellant space rocket and launching the country’s first military surveillance satellite.
Led by the allies’ Deterrence Strategy Committee (DSC), the discussion-based Table-Top Exercise (TTX) is set to take place in the U.S. in the latter half of February, as the two sides agreed to hold it annually at a bilateral defense ministerial meeting in November last year, according to the ministry.
Yonhap
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