BUCKSPORT — The North Korean government recently said that it will not negotiate any nuclear deals until it has rockets that can reach the East Coast, presumably with hydrogen bombs. Though President Trump managed to dial back the “fire and fury” rhetoric against Pyongyang during this week’s stop in South Korea, the whole world is nauseated and terrorized at the possibility that he’ll resume the ratcheting toward a pyromaniac showdown with Kim Jong Un. It is incumbent on all Mainers to unite in total support of Sen. Susan Collins, Sen. Angus King and Rep. Chellie Pingree and their efforts to contain him.

Alex Wellerstein, a professor at the Stevens Institute of Technology in Hoboken, New Jersey, and author of the blog nuclearsecrecy.com, has developed a simple computer program called Nukemap. It can predict the human casualties and damage pattern on any city hit by a nuclear weapon of any size, dropped from any height, at any time of day or night.

What would happen if Portland, Maine, were hit by the same Little Boy that hit Hiroshima with the equivalent of 15,000 tons of TNT? Imagine a bright August weekday morning with people everywhere hard at work or streaming all over the city. About 65,000 people live in Portland, but almost double that number would be in the city for work or play. Using Nukemap to simulate an explosion the size of Hiroshima at around 2,000 feet over Monument Square, the effects are soul-wrenching.

Initial casualties are predicted to be about 30,000 and the number of injuries about the same. The fireball would be about 1,000 feet across: from Cumberland Avenue to Spring Street and from the Maine College of Art almost to City Hall.

The air blast zone, where the pressure would exceed 20 pounds per square inch, would be almost a mile across. One square foot would bear a pressure of nearly 3,000 pounds, a 4×6 window almost 35 tons. Within this area, heavily built concrete buildings would be severely damaged or demolished and nearly everyone would be killed. This would destroy the Arts District and extend well into East Bayside, West Bayside and Parkside.

The Old Port would also be demolished and debris blown well out onto the docks and beyond. Even large cruise ships could be blown over. Many beautiful old churches would be just heaps of stone. Several major banks’ headquarters and the Cross Arena would be unrecognizable, as would the Time and Temperature building and the Westin Portland Harborview Hotel, with its multiple communications antennas.

The air blast zone is where pressures over 5 psi can collapse most residential buildings, and cause widespread fatalities and universal injuries. It would extend as far as the University of Southern Maine to Munjoy Hill and well into the West End, including Maine Medical Center.

Hundreds of gorgeous old wood and brick houses, apartment buildings and historic landmarks would be obliterated, and debris hurled would cause injuries over 2 miles away in all directions. Mercy Hospital would have major blowout damage and patient and staff casualties. Exposed wooden structures would catch fire, which could cause a regional firestorm if there were a hot dry wind, and recent summer drought. Major roof damage from the air blast could occur 3 miles away, and isolated tile or shingle damage up to 5 miles away.

The nuclear radiation zone, where 500 rem of total body radiation can kill 50 percent to 90 percent of those exposed without immediate medical treatment, over several hours to several weeks, would extend 1.2 miles. It would affect anyone out in the open from the Portland Observatory, to Maine Med, into the West End and out onto the Casco Bay Bridge.

The thermal radiation zone is where any exposed skin will suffer third-degree burns, which can be painless because they are full thickness, which destroys the nerves. They can develop into very painful and deforming keloid scars, which can necessitate later amputation. A swollen, deformed face from the 1945 detonation of Little Boy was called a “brown bag Hiroshima face.” Burns conformed to the dark patterns on clothes. Shadows of people were engraved like negatives on concrete walls or charred telephone poles.

Presumably such a burn would cause blindness in an open eye. Occasional living victims of the Hiroshima blast were found with boiled eyes hanging out of their sockets, and tongues so swollen they blocked their breathing. There are no specific data on the incidence of post-traumatic stress disorder, but some writers consider it to be universal. Traumatic brain injury from the initial supersonic blast wave over about half a mile has not been quantified.

We must all ensure that nothing like this can ever happen again – in North Korea or anywhere else.