Subscribe for 33¢ / day

We wrote last month about the science community’s Doomsday Clock, which has been ticking away since the late 1940s, driven by the deadly mix of global politics and nuclear weapons.

In that editorial we pointed out that doomsday could happen when the big and little hands coalesced at 12 o’clock. For the past couple of years, the minute hand had been hovering around 3 minutes to midnight, but recent saber-rattling had pushed it 30 seconds closer to the hour of doom.

Nothing has happened in the past 40 days or so to change that. If anything, the minute hand is even closer to 12, as the leaders of this nation and North Korea — and now, apparently, Iran — have exchanged even more provocative threats.

Of particular concern at the moment is the North Korean regime’s increasing the frequency with which it is conducting missile tests, provoking Donald Trump's Defense Secretary Jim Mattis to warn North Korea of an "effective and overwhelming" response if Pyongyang fired off a nuclear weapon. What makes this especially alarming is Defense Secretary Mattis’ favored nickname — “Mad Dog.”

Threats from any nation are not idle, by any means. The planet’s nuclear-armed states have around 15,000 warheads, the majority of them belonging to the United States and Russia. About 10,000 of those warheads are in active military service, but really, how many nuclear bombs does one need to obliterate mankind?

There are five major nuclear-weapon states in the world — China, France, Russia, United Kingdom and the United States. There are also four other countries that have nuclear weapons — Pakistan, India, Israel and North Korea. These last four countries didn't sign any non-proliferation treaties, and together possess an estimated 340 nuclear weapons.

The United States and Russia hold nearly 90 percent of the nukes, and so far, cooler heads have prevailed when it comes to triggering an exchange of nuclear weapons.

Still, the potential for unbelievable calamity is there. It is estimated the U.S. and Russian nuclear arsenals combined have power equating to 6,600 megatons. This is a 10th of the total solar energy received by Earth every 60 seconds.

According to the NukeMap website, the dropping of the largest nuclear bomb in the current U.S. arsenal would kill 1.4 million people in the first 24 hours. A further 3.7 million would be injured, as the thermal radiation radius fanned out.

Russia’s largest bomb, if dropped on New York City, could kill 7.6 million people and injure 4.2 million more. The nuclear fallout could reach and impact millions more people in places downwind.

Both America and Russia's nuclear arsenals are regulated by treaties limiting the numbers and kinds of warheads and delivery systems they have. However, if either country expands its nuclear capacity beyond agreed-upon limits — as both Presidents Trump and Putin have hinted — it could negate all agreements, thus opening the door to another Cold War, or worse, World War III.

That’s why the school-boy rhetoric between the leaders of North Korea and the United States is so very dangerous, and has re-energized the hands of the Doomsday Clock.

To their credit, cooler heads in the Trump administration are trying to prevail. Secretary of State Rex Tillerson insists back channels are still open to discussions about how to defuse a potentially disastrous situation.

For folks who’ve been through A-bomb drills and the first Cold War of the 1950s, this is like a bad horror film in which actors go down into a dark cellar, which everyone watching knows is full of demons.