Seventy-two years after the United States dropped atomic bombs on Hiroshima and Nagasaki the specter of nuclear war once again hangs over the world. In the span of a few hours, both the United States and North Korea made nuclear threats against one another. Donald Trump went first, saying “North Korea best not make any more threats to the United States. They will be met with fire and fury like the world has never seen.”

Shortly after Trump’s “fire and fury” comments, North Korea’s KCNA carried a statement from the Strategic Force of the Korean People’s Army (KPA) that threatened the “air pirates” stationed at Guam with a nuclear strike. The KCNA statement closed with the warning, “[The United States] should immediately stop its reckless military provocation against the state of the DPRK so that the latter would not be forced to make an unavoidable military choice.” While KCNA did not reference Trump’s comments, the timing of its release creates the impression that the two countries had issued dueling nuclear threats.

At their core, both Trump’s “fire and fury” comment and the KCNA statement are deterrent threats, which seek to prevent a certain action by threatening a high cost in retaliation. If the target of the deterrent threat takes the action that the threat issuer deems unacceptable, then the former will suffer a worse fate. The credibility of deterrent threats depend on whether or not the targeted state believes that the issuer will follow through on its rhetoric.

While both Trump and KCNA issued deterrent threats, the quality of the threats are markedly different. Trump’s threat is incredibly vague both in terms of what the threat is trying to prevent and what costs the United States would inflict on North Korea in response. A lack of clarity about what Trump wants to deter could prevent North Korea from taking any escalatory actions, but given the high stakes involved for North Korea it is unlikely to view Trump’s threat as credible. Kim Jong Un will keep making nuclear threats because the vulnerability of the United States to nuclear attack deters America from attacking North Korea in the first place.

Ambiguous deterrent threats can work, but such threats are not usually issued by powerful countries. Meanwhile, the uncertainty created by Trump’s comment is not reassuring to the other parties involved in the North Korea issue. The “fire and fury” statement could complicate relationships with U.S. allies if they feel that Trump’s rhetoric increases the likelihood of escalating the crisis and putting their security at risk. Additionally, efforts to convince China to do more to help the United States solve the North Korea problem could suffer if Trump’s rhetoric is seen as an indication of unpredictable U.S. policy.

In contrast to Trump’s ambiguous language about “fire and fury,” the KCNA statement is very detailed and precise. The statement references specific U.S. actions that North Korea wants stopped and says what costs North Korea is prepared to inflict. Flights of strategic bombers out of Guam are interpreted as “muscle-flexing in a bid to strike the strategic bases of [North Korea]. This grave situation requires the KPA to closely watch Guam…and necessarily (sic) take practical actions of significance to neutralize it.” In order to neutralize this threat, the KPA is preparing an operational plan to make “an enveloping fire at the areas (sic) around Guam with medium-to-long-range strategic ballistic rocket (sic) Hwasong-12 in order to contain the U.S. major military bases on Guam.”

There is little ambiguity in the KCNA statement. The deployment of strategic bombers to Guam is seen a major threat to North Korea’s security. In the event of a conflict, the KPA plans to neutralize the threat with nuclear-armed ballistic missiles to both prevent the bombers from carrying out an attack on North Korea and send a “serious warning signal to the U.S.” Pyongyang is trying to deter strikes by aircraft stationed at Guam by threatening to destroy the island’s air force base with nuclear weapons. An unprovoked North Korean attack against Guam is not credible because it would invite a devastating retaliation, but their threats to attack the U.S. base early in a conflict are credible. Such threats can deter the United States by making the costs of preemptive action prohibitively high.

Trump’s bombastic statement about “fire and fury” is a clumsy threat that is unlikely to change North Korea’s calculus or behavior. Ambiguity can be a very valuable tool for deterrence, but ambiguous deterrent threats are ill-suited for addressing America’s North Korea problem. Trump doesn’t have to give up his colorful language, but if he wants his deterrent threats to be effective he needs to be precise about what actions the United States deems unacceptable. He should leave the “fire and fury” talk to the North Koreans.