Photo/IllutrationThe Asahi Shimbun

SEOUL--In response to the heightened threat from North Korea, the United States and South Korea will conduct large-scale joint military exercises for the second consecutive year this spring, rather than biennially.

The decision comes in the face of a combative North Korea, which has been engaged in nuclear and missile development programs, several U.S. and South Korean military sources said on Feb. 25.

The joint military drills have been held annually in the spring to coordinate their operations, including dispatch of U.S. troops for reinforcements.

In even-numbered years, landing operations, a key component of the joint drill, have been conducted on a large-scale basis, while they have been run on a smaller basis in odd-numbered years.

In 2016, as many as 290,000 South Korean troops and 15,000 U.S. troops participated in the joint drill, which was called the biggest of its kind ever.

Following the exercise, North Korean continued to conduct nuclear weapons experiments and ballistic missile launches.

In this year’s major drill scheduled to start on March 1, the U.S. nuclear-powered aircraft carrier Carl Vinson will participate, as an aircraft carrier did in the 2016 exercise.

The United States and South Korea also plan to conduct an exercise based on the assumption that they will utilize the Terminal High Altitude Area Defense (THAAD) missile system, which be deployed this year. China is strongly opposed to the deployment.

On Feb. 14 in the national assembly, the South Korean National Defense Ministry said in this spring’s joint drill it plans to boost exercises to deal with North Korean nuclear and missile development programs and prepare capabilities for retaliatory strikes.

The ministry also said that it is discussing with the United States the deployment of strategic arms.

Both nations are acting on the assumption that North Korea will continue to conduct ballistic missile launches. To deter North Korea’s provocative acts, U.S. forces have begun to deploy strategic arms, including its most advanced systems, in the western Pacific region.

The Carl Vinson, based in California, is scheduled to arrive in Guam this month. In addition, B-1B strategic bombers and F-22 stealth fighters were recently deployed in Guam and the U.S. forces’ Kadena base in Okinawa Prefecture, respectively, in rotation. F-35B stealth fighters were also deployed to the U.S. forces' Iwakuni base in Yamaguchi Prefecture.

The X-band radar system, to detect ballistic missile launches, has left a U.S. naval base in Hawaii and, at present, is said to be deployed at sea in the western Pacific.

“All of these arms systems can immediately deal with emergencies that could occur on the Korean Peninsula,” said a source related to U.S.-South Korea relations.

The deployment of strategic arms is also aimed at coping with unstable security situations created by China.

Meanwhile, the online edition of the North Korean newspaper Rodong Sinmun said on Feb. 24, “As long as the drill is not suspended, we will continue to strengthen our national defense capabilities centering on a nuclear force to defend our country.”