However, North Korean leader Kim Jong-un has yet to display that his regime does indeed possess the technological knowledge needed to successfully fire a nuclear-tipped ICBM to hit the U.S. Miniaturizing a nuclear warhead to fit atop a ballistic missile is just one hurdle, and ensuring it does not tear apart upon atmospheric reentry (no small feat) is another. What is more urgently concerning is the fact that North Korea already has all of the technology it needs to start a damaging war with the U.S. via its short- and medium-range missiles. If America were to go to war with North Korea, it would most likely be in defense or aid of America’s East Asian allies.

The geographic proximity of Japan and South Korea to the hermit kingdom mean artillery or short- and medium-range missiles would suffice if Pyongyang were to conduct a damaging first strike. Unlike trying to hit the U.S. mainland, a target more than 5,000 miles away, Seoul and Tokyo, 121 miles and 798 miles respectively from the North Korean capital, present easier and similarly high-value targets, especially given both cities’ sizable populations.

Moreover, the strong defense alliance between the U.S. and both countries provides tempting targets with which North Korea could inflict pain. The U.S. military has a strong presence in both countries, with more than 60,000 troops stationed at various bases throughout Japan and South Korea. An attack on naval base Yokosuka outside of Tokyo or Yongsan Garrison on the outskirts of Seoul would result in a significant number of American lives lost in addition to the enormous loss of Japanese and South Korean lives. In Seoul, the sheer number of U.S. artillery shells and the positioning of artillery would make it difficult to adequately defend a North Korean nuclear attack. Although U.S. military installations in Tokyo do not have the same tactical conundrum, the short- and medium-range missiles capable of striking Tokyo would inflict a heavy human cost.

The cornerstones of America’s alliances with Japan and South Korea are their mutual defense treaties. If either Japan or South Korea were attacked, the U.S. would be obligated to come to their aid—and therefore into a war with North Korea. A war with North Korea on the Asian continent sparked over an attack on an American ally would incur the same grave costs of a direct conflict between Washington and Pyongyang, but with the added complexity of navigating potentially trilateral military interoperability and the political will and cost-benefit calculations of three democratic societies.

This growing threat of a conflict and North Korea’s increasing belligerence should serve to strengthen ties, bilaterally and trilaterally, between Washington, Tokyo, and Seoul. The deployment of the Terminal High Altitude Area Defense (THAAD) anti-ballistic missile system in South Korea and continued U.S.-Japan cooperation to ramp up efforts against the dictatorial Kim regime are steps in the right direction. Maintaining positive relations between the U.S. and its East Asian allies should be a top priority for the Trump administration to counter North Korea’s aggression.

As frightening as ICBMs sound, Pyongyang already possesses all the weapons it needs to draw America into a war. The question is whether the U.S. and its allies will continue to strengthen the tools required to deter such a conflict.

Hannah Suh is the program manager of the Asia-Pacific security program at the Center for a New American Security.