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Chapter 1: Building The Bomb


Trinity test explosion

Photo Credit: Trinity and Beyond: The Atomic Bomb Movie

December 7, 1941...a date which will live in infamy.


On that day, the Japanese launch a surprise military strike on the United States Naval Base located at Pearl Harbor in Hawaii.  Four battleships are sunk, numerous other vessels are damaged or destroyed, 188 aircraft are wiped out, over 2400 Americans are killed and more than 1100 others are wounded.


Aftermath of the attack on Pearl Harbor

Photo Credit: Smithsonian National Air & Space Musem

In response to the attack, the United States officially declared war on Japan and aligned themselves with Great Britain, France and Russia to battle the Japanese and the Germans in the Pacific Theater.

With that, America was now officially a part of World War 2.  This action also accelerated the planned development of the atomic bomb in the US and on December 28, 1942, President Franklin D. Roosevelt authorized the formation of The Manhattan Project to combine allied research into a single entity, with the goal of weaponizing nuclear energy.


Physicist J. Robert Oppenheimer, director of the Los Alamos Laboratory

Photo Credit: Wikipedia

With the formation of The Manhattan Project, research facilities were set up in remote locations across the United States including Washington, Tennessee and New Mexico - which is where history would be made a little over 2 years later.

Physicist J. Robert Oppenheimer, who would come to be known as "the father of the atomic bomb", was already working on the concept of nuclear fission when he was named the director of the Los Alamos Laboratory in Northern New Mexico.

Los Alamos Laboratory (otherwise known as "Project Y") was a secret site located in desert, about a hundred miles away from the city of Albuquerque.  The site was chosen at Oppenheimer's recommendation due to the mild climate, low population density and distance from US west coast - which could ensure it wouldn't be vulnerable to another attack by Japan.

By 1944, over 6000 scientists and engineers from universities & research labs across the US were hard at work on the development of the world's first ever nuclear weapon.  And by the spring of 1945, The Manhattan Project looked to be on the brink of success.


April 12, 1945, US President Franklin D. Roosevelt dies suddenly

Photo Credit: Greensboro Daily News

Following President Roosevelt's sudden passing on April 12, 1945, Vice President Harry Truman is sworn into office as the new Commander-In-Chief and briefed on the progress of The Manhattan Project.  Just weeks later, Germany unconditionally surrendered their war effort and although the Japanese were near defeat with supply lines cut off and thousands dead, it was expected that their plan was to fight to the bitter end.

A costly invasion of Japan seemed likely, but some US policy makers felt that the successful delivery of one or more atomic bombs might convince the Japanese that resistance was pointless.


Trinity test explosion, Los Alamos, New Mexico

Photo Credit: Los Alamos National Laboratory

Flash forward to mid-July...the Trinity Test.

Preparation for the test began on July 12 with the plutonium core being taken to the test area, with the non-nuclear components following closely behind.  Engineers spent July 13 assembling "the gadget" (as would come to be known) and by 5pm on July 15, it had been hoisted to the top of the 100-foot tall firing tower.

And at precisely 5:30am on Monday, July 16, 1945, the atomic age began.


While staff & observers watched anxiously, "the gadget" exploded over the New Mexico desert, vaporizing the tower and turning the asphalt at the base of the tower into green sand. 


J. Robert Oppenheimer, General Lesley Groves and other staffers at "ground zero" of the Trinity Test several weeks after the test, showing the remains of part of the test tower.

Photo Credit: United States Army Signal Corp

Releasing over 18 kilotons of power, the sky was lit up brighter than a thousand suns, with some observers suffering temporary blindness even though they were watching through dark glass.

Seconds after the explosion, came a huge shockwave, sending searing heat across the desert which knocked several observers to the ground.  The shock was so powerful that a steel container located a half-mile away & weighing over 200 tons was knocked over.

As the orange & yellow fireball stretched up and spread, a second column - narrower than the first - rose and flattened out into a mushroom shape, providing us with the visual image that we've come to associate with the atomic age.

The Trinity Test was deemed a success.


Trinity test explosion, showing full mushroom cloud

Photo Credit: Los Alamos National Laboratory

Once word of the successful test made its way to President Truman, he believed that the threat of a nuclear attack could be used to force the Japanese to end their war effort.  On July 26, 1945 - along with the Chinese President and Prime Minister of Great Britain - Truman issued "The Potsdam Declaration" which called for Japan to unconditionally surrender or "face prompt and utter destruction."

The Japanese rejected the offer on July 29, 1945.


B29 Bomber, "Enola Gay", which dropped the first atomic bomb on Hiroshima, Japan

Photo Credit: Time Magazine

In the early morning hours of August 6, 1945, a B29 Bomber - "Enola Gay" - took off from Tinian Island and headed northwest towards the Japanese islands, over 1500 miles away.  On board was a 9700 pound uranium bomb nicknamed "Little Boy" which was destined for the city of Hiroshima, an important military and communications center with a population of nearly 300,000.

As the Enola Gay neared its target, the aircraft climbed to an altitude of 31,000 feet at at 8:15am, released its payload.  Just 43 seconds later, a huge explosion lit the morning sky as "Little Boy" detonated 1900 feet above the city.

Little Boy killed 70,000 people instantly and injured another 70,000.  The bomb caused total devastation for 5 square miles, with almost all the buildings in the city either destroyed or damaged.


Destruction in Hiroshima following the dropping of an atomic bomb on the city, August 6, 1945

Photo Credit:

Within hours, radio & TV stations in America began broadcasting a statement from President Truman, informing the public that the US had just dropped the world's first nuclear bomb - with more power than 15,000 tons of TNT - on the Japanese city of Hiroshima.  The statement went on to say that if Japan still refused to surrender, the US would attack additional targets with "equally devastating results".

Three days later, on August 9, 1945, the scene would repeat itself.

Once again, a B29 Bomber - "Bock's Car" - loaded with a 10,000 bomb, nicknamed "Fat Man", took off from Tinian and headed towards its primary target of Kokura Arsenal on the northern coast of Kyushu Island.  However, bad weather and anti-aircraft fire forced the pilot to divert to his secondary target:  the city of Nagasaki.

At an altitude of 29,000 feet at 11:01am, "Bock's Car" released "Fat Man" which exploded 43 seconds later roughly 1600 feet over the city with the force of 21,000 tons of TNT.  "Fat Man" killed 40,000 people, injured over 60,000 others and destroyed 3 square miles of the city. 


Mushroom Cloud over Nagasaki

Photo Credit: Nagasaki Atomic Bomb Museum

On August 14, 1945 - just five days later - Japan officially surrendered, putting an end to the war that had begun for the United States with the surprise attack on Pearl Harbor in December 1941.

At this point you're probably wondering, "What does any of this have to do with Las Vegas?"

Don't worry...we're getting there.

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