Defense Secretary James Mattis. Photo: AFP/Getty Images

Defense Secretary James Mattis on Wednesday defended the Pentagon’s request to develop a new, smaller nuke, saying such a weapon could deter North Korea from striking the U.S. with a small nuclear weapon of its own.

Development of the new low-yield nuke is suggested in the Pentagon’s new Nuclear Posture Review, and Wednesday Mattis was asked if the smaller weapons would make the military more likely to use nukes than it is now.

He said the goal of the new weapon would be deterrence. “We believe that some nations could miscalculate — one in particular,” Mattis said, seeming to refer to North Korea. “That nation could assume that if they used, in a conventional fight, a small-yield bomb, we would not respond with a very large-yield bomb.”

He continued: “Our response to this is to make a small-yield bomb and say, ‘Don’t miscalculate.’ It’s a deterrent.”

Critics say low-yield nukes are more likely to be used than their high-yield counterparts. Andrew Weber, assistant defense secretary for President Obama, told the Times, “The new plan is a fiction created to justify the making of new nuclear arms. They’ll just increase the potential for their use and for miscalculation. The administration’s logic is Kafkaesque.”

Another point of contention: The so-called low-yield nuclear weapons may be smaller than the biggest in the U.S. arsenal, but they could cause the same damage as the bombs dropped on Hiroshima and Nagasaki.