President Trump’s objective of getting North Korea to abandon its nuclear arsenal is clear. His strategy for achieving that goal, however, is not.

Even less clear are Trump’s communications to the world, and North Korea, about American intentions. He has flip-flopped and changed his tune on North Korea multiple times in just his first 10 months in office, making it impossible for anyone to know what he will do next. Effective foreign policy, on the contrary, requires the president to signal credible and consistent assurances to allies and threats to adversaries.

Trump’s recent trip to Asia and his designation of North Korea as a state sponsor of terrorism, unfortunately, reveal either an inability or disinclination to conduct foreign policy in this manner. The consequences of Trump’s inconsistency are potentially dire.

Prior to the 2016 election, then-candidate Trump characterized his North Korea strategy as "What I would do very simply is say, China, this is your baby. ... You solve the problem." Months later the president appeared to abruptly end that strategy, tweeting, “I greatly appreciate the efforts of President Xi & China to help with North Korea, it has not worked out. At least I know China tried!” During his recent trip to Asia, however, the president changed back to an earlier refrain: “ China can fix this problem quickly and easily.”

On the diplomatic front, in June of this year Trump noted, “The era of strategic patience with the North Korean regime has failed, many years it has failed. Frankly, that patience is over.” A month later he offered an answer to what might come next: “North Korea best not make any more threats to the United States,” or else “[t]hey will be met with fire and fury like the world has never seen.”

Then, during his recent Asia trip, he again changed course. Instead of elaborating on his implied military threat and trying to amplify its coercive power, Trump called for “progress, not provocation ... stability, not chaos, and ... peace, not war.” Those words sounded a lot like a call to the hard and slow work of diplomacy. Bolstering that notion, during the trip Secretary of State Rex Tillerson indicated that Trump had invited the North Korean regime to direct negotiations; an extension, perhaps, of the “ direct contact” that Trump appeared to have ruled out previously but that the secretary said had in fact been ongoing.

But again on Monday, Trump reversed course yet again, declaring North Korea a state sponsor of terrorism and imposing further sanctions on the regime.

So what is the Trump administration’s strategy towards North Korea? Does China play a critical role or not? Have diplomatic means and patience been abandoned? Is the U.S. prioritizing direct talks with the North Korean regime or will only threats and force resolve the situation? In the past year, the president has suggested the answer is “yes” to each of those strategic options. At times, he has said both yes and no to the same option at the same time.

If Americans cannot determine what the president’s strategy is, then how can the North Korean regime? Media reports indicate that the North Koreans are indeed confused by Trump and have contacted former American officials trying to ascertain what exactly Trump is doing.

Trump’s defenders argue that his vacillations are strategic, designed to pressure North Korea into negotiations by threatening “ devastating” attacks. But Trump’s threats have been anything but clear and credible.

Not only does North Korea have trouble understanding Trump, his threats are in fact empty. Analysts agree the United States has no real military option at this point. According to a Pentagon assessment and other analyses, any attempt to eliminate North Korea’s nuclear arsenal by force would require a ground invasion, likely resulting in hundreds of thousands of deaths in the first few days of conflict and creating a significant risk that North Korea would use nuclear weapons against Seoul and Tokyo.

Nor is there any reason to believe that re-designating North Korea a sponsor of terrorism or imposing additional sanctions will have much impact. Indeed, the very fact that North Korea was able to develop nuclear weapons while laboring under heavy sanctions over decades makes clear how unlikely it is that additional penalties will encourage Kim Jong Un to change course.

In light of the facts, Trump’s rhetorical inconsistency makes conflict more likely, not less. If the North Koreans can’t figure out what Trump’s strategy is, but they start to believe his threats about using military force, then the risk of a North Korean pre-emptive strike rises significantly. The risk of U.S. miscalculation also rises. If North Korea begins preparations to defend itself against what it believes is an imminent American attack, the United States might misread the signs and think North Korea was about to attack, thus setting off a conflict that neither side desired.

Instead of flip-flopping between approaches, the president needs to focus on sending North Korea consistent and clear messages. If he doesn’t, Kim Jong Un could miscalculate, and that’s a nuclear mistake we cannot afford.

Erik Goepner, a retired colonel from the U.S. Air Force, is a visiting research fellow at the Cato Institute. A. Trevor Thrall is a senior fellow at the Cato Institute’s Defense and Foreign Policy Department and associate professor at George Mason University’s Schar School of Policy and Government.

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