Last week, while I was sleeping peacefully in a Tokyo hotel room, a missile fired by North Korea passed over the Japanese island of Hokkaido before crashing into the Pacific Ocean.
As always, Japanese reacted with dismay, and indignation. The boy with the nuclear toy who heads the regime in Pyongyang is driving nerves to a frazzle in the Land of the Rising Sun. Shortly after the missile flew, he detonated a 6.3-magnitude hydrogen bomb in the bowels of the North Korean earth, causing tremors a hundred miles away, and worsened the skittishness.
Japanese, in large measure, trust their security to the 'nuclear umbrella' provided by the United States. Of course, it also does not forget to tie its camels: the Japanese Self-Defence Force is actually a very efficient military, with first rate technology.
But is that enough deterrence against a nuclear-armed adversary? Should Japan itself build nuclear weapons as a warning to its adversaries that atomic adventurism will get a matching and overwhelming response?
You have to travel to Hiroshima, the city that suffered the world's first nuclear attack, to understand why most Japanese are so opposed to atomic weapons that some do not even want to see their electricity come from nuclear energy.
On the morning of Aug 6, 1945, a US B-29 bomber, the Enola Gay, arrived over Hiroshima's South Bay's clear skies with a deadly cargo given the innocent name of Little Boy. The city was chosen for the first atomic bombing because the surrounding hills would concentrate the impact of the blast, which took place at 600m above ground.
Equivalent to 16 TMT, the blast at 0815 hours destroyed 70 per cent of Hiroshima's buildings, and killed more than 70,000, with thousands more to perish in subsequent years.
Mrs Yoshiko Kajimoto, now a sprightly 86, experienced the blast first-hand. She knows something of wars: She had just entered secondary school when the Second Sino-Japanese War broke out and in the sixth grade when the Pacific War, as Japanese call World War II, broke out. And she was in the 9th grade when the bomb arrived.
Middle school kids were mobilised for the war effort. For this reason, she was in a factory making propeller parts, 2.5km from the blast centre when the moment came.
"It was a clear day without the trace of a cloud," she said, hands and voice steady as she recounted the trauma. "It had been warm since early morning and there were no warnings of an air raid."
Then, a flash of light.
"The faces of my parents and my grandfather passed before my eyes and I thought I was dead. It was as though Earth had exploded."
As she had been trained to do, Mrs Kajimoto pressed her fingers to her eyes to prevent them from falling out of their sockets, as the shock wave arrived moments later, meanwhile trying to scramble to safety under the machines.
"My body was lifted up and I passed out of consciousness. When I came to, my friend, stuck under a machine was whimpering: 'Help me, Mother. Help me, Teacher!' My shoulders and legs were trapped. I shook my head and the ash fell from my mouth. The flesh had been ripped off my bones. The factory roof had collapsed. I knew I was alive only because of the pain. People had gone insane. In the distance, I heard someone wail: 'Hiroshima is gone'."
Mrs Kajimoto tore off her blouse to put a tourniquet on her bleeding friend, and used her school headband to fasten it further. Around her was a scene so ghoulish that it was worse than the worst nightmares.
People had their nails ripped out, faces had puffed up like balloons, lips had turned inside out. A fellow student approached her, one hand holding a nearly torn-off arm. Suddenly, she knelt before her, and slumped to the ground, dead.
Fires raged everywhere. A mother holding a dead baby was spinning around, insanely.
Then, incredibly, the 14-year-old felt fear leave her as she stepped over bodies and on shiny skin as she helped carry friends to nearby Oshiba Park.
Then, the cremations started and a foul smell spread through the city. There were maggots everywhere, including on her own body.
On the third day, she heard her own neighbourhood was safe, and she staggered towards her home, meeting her father along the way. He had gone to the factory and turned over each body as he looked for her. Seeing her, he broke down and extracted a ball of rice he had been carrying in his pocket as a good luck charm.
For the next few weeks, she was bed-ridden, her grandmother removing maggots from her body with chopsticks.
Two months later, a doctor arrived to remove glass shards from her body. A year and a half later, the father died vomiting blood.
"He had probably been affected by the radiation from walking three days in the city," she said. "Those days there was no concept of radiation, because it is colourless and odourless."
Mrs Kajimoto herself suffered gastric cancer in later years and had two-thirds of her stomach removed.
Then peace arrived, and so did poverty. She had to provide for three brothers and food was frequently short.
"For the dead it was hell. For the survivors it was hell too."
Mrs Kajimoto's husband died 17 years ago, and she has two daughters, eight grandkids and two great grandchildren. Her fortunes have improved but for five decades, she said, she didn't want to talk about her experience, until a grandson convinced her she must tell her story. That's how I got to hear of it.
"I do not ask for disarmament, but I demand abolition of nuclear weapons," she told me. "Nuclear weapons are an absolute evil and cannot exist with human beings. I do not want Hiroshima, or Nagasaki, to be repeated anywhere."
"Am I concerned over the North Korean situation? Of course, I am. And I believe, that is the sentiment with the young as well. I say that Prime Minister Shinzo Abe should visit North Korea (for talks) even at the risk of his life."
Is this point of view limited to the few thousands still around who saw the curse of Hiroshima? Not hardly. After a week in Japan, I'd say that there are millions who share the same view.
Japan has all the technology in place to build a nuclear arsenal. From the moment a decision is taken to having ready bombs will probably take a few weeks, no more. But it will be a brave Japanese prime minister who orders those final turns of the screws for Japan's first atomic bomb.