The possibility of a U.S. military strike against North Korea has dominated the news in the United States and South Korea — and for a good reason. The Trump administration now appears to be downplaying the idea that it is considering a military strike to prevent Pyongyang from crossing the ICBM threshold. But it’s hard to ignore the consistent signals that senior officials had been sending over the past several months. 

National Security Adviser H.R. McMaster and others have been talking about a “preventive war,” saying we are “running out of time” to solve the North Korea problem, and that North Korea has brought the world "closer to war.” President Trump, for his part, has warned that the U.S. military is “locked and loaded” and threatened to “totally destroy” North Korea.

Recently the administration withdrew Victor Cha’s nomination to be ambassador to South Korea, reportedly because of his objection to a “bloody nose” strike. Despite appearances at the Olympics, we are now closer to a war on the Korean Peninsula than at any time since 1994, when the Clinton administration considered a military strike to destroy North Korea’s Yongbyon nuclear complex.

As former Central Intelligence Agency analysts, with combined 45 years of experience in studying the North Korean regime, we believe that any military strike against North Korea is likely to unleash a series of events that could lead to devastation and massive casualties as well as undermine Washington’s “maximum pressure and engagement” strategy. We work at three different think tanks and don’t see eye to eye on everything, but on this issue we are in total agreement.

A preventive U.S. attack — one that would be conducted without any indication of an imminent North Korean attack — would not eliminate North Korea’s nuclear threat to the American homeland nor guarantee regional stability and security. In fact, a strike would reinforce Pyongyang’s determination to hold onto its nuclear capability, further consolidate Kim’s rule and affirm the regime’s narrative about a “hostile” United States.

Unlike the situation in 1994, we now face a North Korea that has a potential stockpile of up to 60 nuclear weapons with a variety of ballistic missiles to deliver them. Even with clear signaling from the U.S. that a strike is not a prelude to regime change, Kim Jong-un is likely to respond with military action, such as an attack on U.S. military bases in South Korea, to show that he will not be intimidated and maintain his aura of strength.  The U.S., in return, would be forced to fight back. This raises the risk that Kim’s nose will not be the only one getting “bloodied.”

The Congressional Research Service estimates there could be 30,000-300,000 deadin the first days of fighting. The casualty figures would be much higher if North Korea used its nuclear, biological and chemical weapons or if China chose to join the conflict. The Seoul metropolitan area's 25 million residents, including 200,000 U.S. citizens, are vulnerable to North Korean conventional attacks, given its location a mere 35 milesfrom the Demilitarized Zone (about the distance between Washington, D.C. and Baltimore or between New York City and Greenwich, Connecticut). Tokyo's metropolitan area, with its more than 36 million residents, is easily within North Korean missile range.

Beyond the immediate loss of human life and property, there are the long-term ripple effects.  A war in Northeast Asia would affect the world’s second, third and 12th largest economies — China, Japan and South Korea — and throw the global economy into a tailspin. Moreover, a war that started because of U.S. action could lead to the collapse of the U.S.-South Korea alliance and the loss of U.S. standing and credibility in Northeast Asia. Washington would be seen as gambling with our allies’ security, particularly as the Trump administration has yet to articulate the military and political objectives, how a military strike would achieve them, the triggering events for an attack, the parameters of military action, and how to mitigate against a North Korean or Chinese military response.

If the U.S. attacked without notifying our allies or over their objections, it would play into Kim Jong-un’s goal of driving a wedge between the U.S., South Korea and Japan. An attack would also feed into Beijing and Moscow’s narrative that Washington, not Pyongyang, is the source of regional instability and tension, and make it more difficult for Washington to ensure future Chinese and Russian cooperation on pressuring North Korea.

The U.S. must remain vigilant to prevent Kim Jong-un seeking to decouple our alliance with South Korea and reunify the Korean Peninsula by force once he has achieved the ability to hit the U.S. with a nuclear-tipped ICBM. But the best way to prevent North Korean aggression is by maintaining strong cooperation with South Korea and Japan, and making clear to Kim that any aggression will be met with an overwhelming response.  We should reserve military action for a situation when we have clear evidence that North Korea is about to attack, proliferates nuclear weapons to terrorist groups, or crosses any other obvious redline. In the absence of such intelligence, we should not strike first.

We still have time to shape Kim’s approach and avert a war through dialing up the heat on Pyongyang. The Trump administration should be credited for the successes of its “maximum pressure” strategy which has strengthened sanctions. A preventive strike would risk those successes, and potentially trigger a costly military conflict that is likely to undermine our ultimate goal of North Korean denuclearization.