RACHEL BRONSON: So in 1939, the world
is in a desperate situation.
The Nazis are on the move.
They seem unstoppable.
ROBERT ROSNER: The Germans attacked Poland, Netherlands,
Belgium, and the French.
They were ruthless.
They demonstrated their ruthlessness.
RACHEL BRONSON: They seem capable and willing to execute
a war of total domination.
And the United States is watching very carefully
what's happening.
ROBERT ROSNER: They understood what
Hitler was capable of doing.
RACHEL BRONSON: So right about this time,
you have the advancement of nuclear science and physics.
Everybody is on the cusp of controlling nuclear energy.
ERIC D. ISAACS: Several German physicists actually
first demonstrated the ability to split the atom.
People like Albert Einstein, people like Enrico Fermi,
Leo Szilard, realized right away the potential
of what that discovery could mean.
RACHEL BRONSON: Suddenly, Germany
stopped the export of Czechoslovakian uranium, which
makes scientists in the United States and the rest of Europe
very nervous about what Germany is up to.
Scientists convince Einstein to write the letter to FDR.
ERIC D. ISAACS: Warning him that if the Germans were
able to develop that discovery, it could actually
lead to building one of the most powerful bombs ever built.
FDR's response to the letter was remarkably prompt.
RACHEL BRONSON: Funding begins to be
put into nuclear research.
The world's greatest scientists are fleeing Europe,
and they're coming to the United States for safety.
And then as the Manhattan Project becomes established,
they come to the University of Chicago,
and they begin to build the pile.
Under Stagg Field, there was a squash court.
It was a heady environment.
You had the world's best physicists
about to unleash nuclear power.
They're also thinking about the implications
of what it will mean being used for the destruction of humanity
and not for peaceful purposes.
The pace was fast.
They were working against the Germans.
They literally believed it was hour by hour, day by day.
They might be behind.
ROBERT ROSNER: They didn't work 40-hour weeks.
They worked two 12-hour shifts every day.
This was going on 24/7 for two weeks.
ERIC D. ISAACS: They understood what was at stake.
They understood that civilization
in the Western world was at stake.
ROBERT ROSNER: The first step was to acquire the materials.
RACHEL BRONSON: Fermi begins to understand
that if they built a reactor with very pure graphite,
they will get the reaction that they're looking for.
ERIC D. ISAACS: The amount was huge, 45,000 bricks, each brick
weighing almost 20 pounds.
RACHEL BRONSON: They're stacking these graphite blocks
that are incredibly heavy.
They've got day laborers who are helping them with it.
They were using uranium.
ROBERT ROSNER: The uranium came in two forms--
one, metallic uranium, the other, uranium oxide.
RACHEL BRONSON: This was the cutting edge,
the bleeding edge of science.
It was happening here.
ROBERT ROSNER: What was really quite
amazing is the short duration during which the pile
was actually assembled.
RACHEL BRONSON: It was a matter of days
where they built that reactor.
ROBERT ROSNER: 15 days, specifically.
ERIC D. ISAACS: The group felt the weight of the country,
if not the world, on their shoulders.
ROBERT ROSNER: The politicians, FDR included,
really did not understand the nature of the beast
that they were funding.
RACHEL BRONSON: Those in the room understood
that they were on the cusp of a revolutionary change in energy.
ERIC D. ISAACS: They had just finished
building Chicago Pile 1 the day before,
literally December 1, 1942.
And Enrico Fermi declared next morning
they would start the actual experiment.
RACHEL BRONSON: On December 2, 1942, Fermi and his team
were able to control and sustain a nuclear chain reaction.
ROBERT ROSNER: A monumental physics achievement.
ERIC D. ISAACS: It would not be too
much to say this is almost as important
as the discovery of fire.
RACHEL BRONSON: It actually wasn't clear what it meant.
They didn't know if they'd be able to weaponize it.
And they didn't know if the Germans had already
weaponized it.
But the fact that they could control the chain reaction
meant it was possible.
ERIC D. ISAACS: Arthur Holly Compton really
drove it as the lead scientist.
He didn't do it alone.
He did it with dozens and dozens of scientists,
and they built, as Einstein would say,
on the shoulders of giants.
It was really, in many ways, the first time,
Big Science was done.
RACHEL BRONSON: And these big efforts
are both exciting and dangerous.
They have enormous implications for good and for evil.
And it's really up to us to figure out
how to manage the risks so that we can reap the benefits.
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