After a mostly quiet year, North Korea test-fired a number of missiles this month, including cruise missiles and its first-known train-launched ballistic missile. South Korea also tested new capabilities, becoming the only non-nuclear power to successfully test a submarine-launched ballistic missile (SLBM).

Seoul emphasized that its tests — some coming on the same day North Korea tested its own missile tech — were not a response to North Korean provocations but part of a schedule following its long-term military development planning. Pyongyang also said its tests were part of plans laid out in Jan. 2021 at its Eighth Party Congress.