It is becoming increasingly clear that foreign policy is not Ted Cruz’s strong suit. From his incomplete thoughts about using “carpet bombing” to defeat ISIS, to his gross misapplication of the late Jeane Kirkpatrick’s writings to justify his proposed policy of leaving in power Syrian dictator Bashar al-Assad, Cruz’s grasp of foreign policy has been repeatedly questioned by national security experts on both sides of the political aisle. Cruz’s weakness in this area was again on display in Saturday night’s Republican presidential debate in New Hampshire, but this time the subject was North Korea.

North Korea’s missile launch was a good test of the candidates’ preparation and instincts on foreign policy because, as Martha Raddatz of ABC News explained, the test had been reported “just moments” before she asked the candidates about the issue.

She directed her first query at Cruz, providing him a golden opportunity to display his competence on the subject. Instead, he swung and missed, bizarrely claiming that “one of the greatest risks” is that North Korea would “detonate that nuclear weapon and set off what’s called an EMP, an electromagnetic pulse which could take down the entire electrical grid on the Eastern seaboard, potentially killing millions.”

EMP is one of the physical effects of a nuclear explosion and it does have the ability to fry electronics. It should, therefore, be somewhere on the list of possible threats and doing more to harden U.S. infrastructure from the effects of EMP would be worthwhile. But, it is nowhere near the top of the list of the most likely or devastating consequences of a nuclear-armed North Korea. It is hard to imagine North Korea conducting a bolt-out-of-the-blue EMP attack and, even if it did, the effects, while serious, would likely be less severe than many more plausible scenarios.

Rather, the greatest near-term threat posed by North Korea’s growing nuclear and missile capabilities is that Pyongyang will increasingly be able to hold the U.S. homeland at risk with the threat of nuclear attack, making Washington less willing and able to challenge North Korea.

Facing a less resolute Washington, North Korea may be tempted to step up its aggressive behavior against U.S. allies in Asia. In recent years, it has sunk a South Korean warship and shelled a South Korean island and, if it believes that it can hold the United States at bay with nuclear threats, it may be tempted to engage in even larger and more provocative attacks. In this case, a resumption of open conflict on the Korean peninsula, including one that would likely entangle the United States (and one that could conceivably escalate to a direct nuclear strike—not merely an EMP) cannot be ruled out.

Furthermore, if America’s allies in the region, such as Japan and South Korea, increasingly doubt whether they can count on U.S. security guarantees, they may feel it necessary to go it alone, building their own indigenous nuclear arsenals and igniting a nuclear arms race in one of the world’s most important geostrategic regions.

Given these more pressing concerns, it is puzzling that Cruz chose to focus his remarks on the more fanciful threat of an EMP attack, calling into question his understanding of national security issues and his judgement more broadly.

Countering the more serious threats posed by North Korea, as other candidates noted, must begin with halting and then rolling back Pyongyang’s nuclear capabilities. The Obama administration’s policy of “strategic patience” has been a disaster and as Florida Senator Marco Rubio ably explained, the appropriate response will require working with China and the rest of the international community to bring more economic and political pressure to bear.

In addition, Washington must develop and deploy regional and homeland ballistic missile defenses to protect against incoming missile attacks and to counter the coercive potential of North Korea’s growing strategic forces.

This is a policy solution that nearly all of the candidates highlighted, including Ted Cruz.

As they say, even a broken clock is correct twice a day.

Matthew Kroenig is Associate Professor of Government and Foreign Service at Georgetown University and a former strategist and special adviser in the Office of the Secretary of Defense. You can follow him on Twitter at @kroenig.

Image: Flickr/Michael Vadon.