Launch on Warning is still official policy. In that context the following reflects the current reality. Without guessing what the preplanned response to aNK launch would be, waiting to see where the landed (and he estimated CEP of the Hwasong-14 is around 30Km, about the distance they claim to miss by), waiting for impact is not in line with how the system is designed to react and respond.
World War Three, by Mistake | The New Yorker
".......The launch-on-warning policy became controversial during the nineteen-seventies, once it was publicly known. The hundreds of missiles based on American submarines, almost impossible to find in the depths of the ocean, seemed more than adequate to deter a Soviet attack. During testimony before the House Armed Services Committee in 1979, Fred Iklé, a conservative Republican who later became a top Pentagon official during the Reagan Administration, said, “If any witness should come here and tell you that a totally reliable and safe launch-on-warning posture can be designed and implemented, that man is a fool.” The Pentagon repeatedly denied that launch-on-warning was American policy, claiming that it was simply one of many options for the President to consider. A recent memoir, “Uncommon Cause,” written by General George Lee Butler, reveals that the Pentagon was not telling the truth. Butler was the head of the U.S. Strategic Command, responsible for all of America’s nuclear weapons, during the Administration of President George H. W. Bush.
According to Butler and Franklin Miller, a former director of strategic-forces policy at the Pentagon, launch-on-warning was an essential part of the Single Integrated Operational Plan (siop), the nation’s nuclear-war plan. Land-based missiles like the Minuteman III were aimed at some of the most important targets in the Soviet Union, including its anti-aircraft sites. If the Minuteman missiles were destroyed before liftoff, the siop would go awry, and American bombers might be shot down before reaching their targets. In order to prevail in a nuclear war, the siop had become dependent on getting Minuteman missiles off the ground immediately. Butler’s immersion in the details of the nuclear command-and-control system left him dismayed. “With the possible exception of the Soviet nuclear war plan, [the siop] was the single most absurd and irresponsible document I had ever reviewed in my life,” Butler concluded. “We escaped the Cold War without a nuclear holocaust by some combination of skill, luck, and divine intervention, and I suspect the latter in greatest proportion.” The siop called for the destruction of twelve thousand targets within the Soviet Union. Moscow would be struck by four hundred nuclear weapons; Kiev, the capital of the Ukraine, by about forty.
After the end of the Cold War, a Russian surprise attack became extremely unlikely. Nevertheless, hundreds of Minuteman III missiles remained on alert. The Cold War strategy endured because, in theory, it deterred a Russian attack on the missiles. McNamara called the policy “insane,” arguing that “there’s no military requirement for it.” George W. Bush, while running for President in 2000, criticized launch-on-warning, citing the “unacceptable risks of accidental or unauthorized launch.” Barack Obama, while running for President in 2008, promised to take Minuteman missiles off alert, warning that policies like launch-on-warning “increase the risk of catastrophic accidents or miscalculation.” Twenty scientists who have won the Nobel Prize, as well as the Union of Concerned Scientists, have expressed strong opposition to retaining a launch-on-warning capability. It has also been opposed by former Secretary of State Henry Kissinger, former Secretary of State George Shultz, and former Senator Sam Nunn. And yet the Minuteman III missiles still sit in their silos today, armed with warheads, ready to go......"