What Was the Cold War, Anyway?

Have you ever heard grown-ups talk about the “Cold War” and wondered if they were fighting with snowballs, ice cubes, or something even colder? You’re not alone! For 45 years, from 1945 to 1991, the world was split in two by a conflict that had almost no direct fighting between its two biggest players, but changed almost every part of life for people across the globe. That conflict is the Cold War, and in this chapter, we’re going to break down exactly what it was, why it started, and how it shaped the world we live in today—no complicated history degree required.

To understand the Cold War, we have to start at the end of World War II, the biggest, deadliest war in human history. For six years, from 1939 to 1945, most of the world’s countries fought on one of two sides: the Allies (led by the United States, the Soviet Union, and the United Kingdom) or the Axis (led by Nazi Germany, Imperial Japan, and Fascist Italy). By May 1945, the Allies had defeated Nazi Germany, and by August 1945, they had forced Japan to surrender after the US dropped two atomic bombs on the cities of Hiroshima and Nagasaki. When the fighting stopped, the world was left in ruins: cities were destroyed, millions of people had died, and most of Europe and Asia needed to be rebuilt from scratch. Just a few months before the war ended, the leaders of the three biggest Allied countries met in a palace in Yalta, Crimea, to decide what the world would look like after the fighting stopped. US President Franklin D. Roosevelt, British Prime Minister Winston Churchill, and Soviet leader Joseph Stalin sat around a table drawing lines on maps of Europe and Asia, deciding which countries would be controlled by which side. At first, they were all on the same team, but they had very different ideas about how countries should be run. The US and

1.1 The End of World War II: The Team That Fell Apart

For six long years, from 1939 to 1945, most of the world fought in the deadliest war in human history: World War II. On one side were the Allies, a team led by three big, powerful countries: the United States (led by President Franklin D. Roosevelt), the United Kingdom (led by Prime Minister Winston Churchill), and the Soviet Union (led by Joseph Stalin). On the other side were the Axis, led by Nazi Germany’s Adolf Hitler, Imperial Japan, and Fascist Italy. The Allies won the war in 1945: first, Soviet soldiers marched into Berlin, Germany’s capital, and forced Hitler to kill himself as his city burned; then, the US dropped two new, extremely powerful weapons called atomic bombs on the Japanese cities of Hiroshima and Nagasaki, killing more than 200,000 people and forcing Japan to surrender.

When the fighting stopped, the world was in ruins. More than 70 million people had died—more than the entire population of California today. Most of Europe’s cities were destroyed, farms were burned, and factories were bombed into rubble. Millions of people had no homes, no food, and no jobs. The three biggest Allied leaders knew they had to make big decisions about how to rebuild the world, so they met in February 1945 at the Yalta Conference, a secret meeting in a palace on the coast of Crimea (a part of the Soviet Union at the time). They sat around a big wooden table with maps of Europe and Asia spread out on it, drawing lines to decide which countries would be controlled by which side after the war.

At first, it seemed like they were all on the same team. But they had very different ideas about how the world should work. Roosevelt and Churchill believed in a system where people could vote for their own leaders, own private property and businesses, and make their own choices about how to live. Stalin and the Soviet leadership believed in a system where all major resources (factories, farms, mines) were owned by the government on behalf of everyone, and the government made all the big decisions to make sure no one was poor or left out. At Yalta, they agreed to split Germany into four parts, each controlled by one of the Allies: the US, the UK, the Soviet Union, and France. They also agreed that countries in Eastern Europe (like Poland, Czechoslovakia, and Hungary) would get to hold free elections to choose their own governments after the war.

But almost as soon as the war ended, the team fell apart. By 1946, it was clear Stalin had no intention of holding free elections in Eastern Europe. Soviet soldiers who were stationed in those countries during the war refused to leave, and Stalin helped communist groups take over the governments of every Eastern European country, turning them into Soviet allies. The US and UK were furious. They had fought the war to stop Hitler from taking over other countries, and now they saw Stalin doing almost the same thing. By 1947, the two sides were no longer cooperating at all. The Cold War had begun.

> 📖 *Print Book Note*: This section opens with a full-page illustrated spread of the Yalta Conference, with captions pointing out each leader’s core priorities: Roosevelt’s note reads “Wants free elections and open trade around the world”, Churchill’s reads “Wants to protect the British Empire and stop Soviet expansion”, Stalin’s reads “Wants a buffer zone of friendly countries to protect the Soviet Union from future invasions”. > > 📱 *Digital Edition Note*: Hover over the Yalta map to see clickable hotspots for each occupied country, with short pop-ups explaining what happened to that country after the war. > > 🤖 *Markdown Tag*: `<section id="yalta" data-tags="WWII, Yalta Conference, Allies, Axis, post-war division">`

1.2 What Is “Ideology”? Two Classrooms, Two Sets of Rules

You might have heard grown-ups talk about “ideology” like it’s a fancy, complicated word. It’s actually pretty simple: an ideology is just a set of core beliefs that a group of people shares about how a country, a school, or even a small group should be run. It’s the set of rules that everyone in the group agrees are the “right” rules, even if other groups think their rules are better.

To make this easy to understand, let’s imagine two 4th grade classrooms, both with 25 students and one teacher, but with totally different sets of rules:

First, there’s Ms. Johnson’s classroom, which runs on rules based on the US’s core ideology of capitalism and liberal democracy:

• Students get to choose their own seats every day, as long as they don’t distract other people.
• Homework is optional: if you want to practice your math skills, you can do it, but if you’d rather play soccer after school, that’s okay too, as long as you keep up with classwork.
• The class has a “class fund” made of money students donated voluntarily. The class votes every month on what to spend it on: some months they buy extra art supplies, other months they buy snacks for a party, and if a student can’t afford a field trip fee, the class can vote to pay for them.
• If someone breaks a rule (like talking during a test), the class discusses what to do about it together. There’s no single person who makes all the rules.

Now, there’s Mr. Petrov’s classroom, which runs on rules based on the Soviet Union’s core ideology of communism:

• The teacher assigns every student a seat at the start of the year, and you can’t change it without permission. The seats are arranged so that students who struggle with math sit next to students who are good at math, so everyone can learn together.
• Every student has to complete all homework assignments, no exceptions. The homework is designed to make sure everyone learns the same skills at the same pace, so no one falls behind.
• The class has a shared fund made of mandatory donations from every student. The class “student committee” (elected by the class, but following rules set by the school) decides how to spend the money: it always goes to things that benefit the whole class, like new textbooks or winter coats for students who can’t afford them. No one gets to vote to spend t