The United States and South Korea have announced that they are canceling large-scale military exercises to support diplomacy with North Korea. U.S. President Donald Trump suspended similar drills after the Singapore summit with North Korean leader Kim Jong Un last year and the failure of last week's follow-up meeting between the two men prompted many observers to expect some move to restore momentum to faltering diplomacy. While we support every effort to promote a peaceful denuclearization of North Korea, it is also critical that regional security and stability not be compromised in the process.

The U.S. and South Korea have held bilateral exercises since the inception of their alliance. The very real fear of a North Korean invasion — a reasonable concern given the North's attack on the South in June 1950 — obliged the two allies to prepare to fight and the more realistic the scenario the more effective the training would be. Those preparations also signal to Pyongyang that any attack would fail, deterring a conflict before it began.

North Korea has long complained about the exercises, arguing that they are practice runs for an invasion, and it has used them as proof of the need to acquire a nuclear capability. Other governments in the region, China in particular, accept that criticism and have urged the allies to halt exercises to reduce tensions on the peninsula and give the North a reason to denuclearize. Of course, China would also benefit if the two countries stopped exercises and the capabilities of the alliance were to be reduced.