The Defeat of Germany ยป The USA Enters the War

What you'll learn this session

Study time: 30 minutes

Edexcel spec: Paper 2 Section A, Investigation A1, Key topic 5

  • Why the USA gave up its neutrality and declared war on Germany in April 1917
  • What American money, supplies, ships and soldiers gave the Allies
  • How the American entry changed Germany's choices
  • How to judge the significance of the US entry into the war

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Why the USA joined the war

When war began in 1914, President Woodrow Wilson kept the USA neutral. Most Americans saw the war as Europe's quarrel. In November 1916 Wilson won a second term as president with the slogan 'He kept us out of war'. Five months later he asked Congress, the American parliament, to declare war. Four things changed his mind.

  • Trade and loans. The British blockade meant that American trade went almost entirely to the Allies. American factories and farms sold them huge amounts of weapons, food and raw materials, and by 1917 American banks had lent the Allies more than 2 billion dollars. The USA was neutral in law, but its wealth was tied to an Allied victory.
  • The U-boats. On 1 February 1917 Germany went back to unrestricted submarine warfare, so American ships sailing to Britain could now be sunk without warning. Wilson cut off diplomatic relations with Germany two days later. In mid-March U-boats sank three American merchant ships.
  • The Zimmermann Telegram. In January 1917 the German Foreign Secretary, Arthur Zimmermann, sent a secret coded message to Mexico. If the USA entered the war, Germany offered Mexico an alliance, money, and help to win back its 'lost territory in Texas, New Mexico, and Arizona'. Room 40, the British code-breakers, decoded the telegram and Britain passed it to the Americans. It was printed in American newspapers on 1 March 1917, and Zimmermann admitted it was real. Americans were furious. The war no longer seemed far away.
  • Revolution in Russia. In March 1917 the Tsar, Russia's all-powerful emperor, was overthrown. Wilson could now present the war as a fight of free peoples against the rule of emperors and generals.

On 2 April 1917 Wilson asked Congress for war, saying, 'The world must be made safe for democracy.' Congress agreed by a huge majority, and the USA declared war on Germany on 6 April 1917.

Key terms:

  • Zimmermann Telegram: the secret German message of January 1917 offering Mexico an alliance against the USA
  • Associated Power: the name the USA used for itself in the war. It fought alongside the Allies but signed no alliance with them
  • The draft: the American name for conscription
  • American Expeditionary Forces (AEF): the American army sent to France, led by General John Pershing

What the USA gave the Allies

The USA was the richest industrial country in the world, with a population of about 100 million. But it was not ready to fight. Its regular army had only about 130,000 men. So its help came in stages: money and ships quickly, soldiers slowly.

💰 Money

By early 1917 Britain was close to running out of the money it needed to pay for American goods. Now the American government itself lent to the Allies, about 7 billion dollars by the end of the fighting. The Allies could keep buying all they needed.

📦 Supplies

American food, steel, oil and weapons crossed the Atlantic in growing amounts. Britain and France could keep their armies and their people fed while the blockade left Germany hungry.

🚢 Ships

The first American destroyers reached Ireland in May 1917. They helped to guard the convoys, just as the U-boat campaign was at its most dangerous.

🎖 Soldiers

A draft law was passed in May 1917, and about 2.8 million men were called up. The first Americans landed in France in June 1917. There were about 300,000 by March 1918 and about 2 million by November 1918.

The American soldiers, nicknamed 'doughboys', were fresh, fit and confident. Pershing insisted that they should fight as a separate American army, not be shared out among British and French units. They were short of experience and of heavy weapons, so they used mostly French guns and aircraft, and many crossed the Atlantic in British ships. By the summer of 1918 around a quarter of a million were landing in France every month. Their part in the fighting of 1918 comes in the lesson The Hundred Days and Why Germany Lost.

What it meant for both sides

📈 For the Allies

1917 was a dark year for the Allies. French soldiers mutinied, Russia was falling apart and Passchendaele brought heavy losses. Through all this, the promise of American men and money lifted morale. The Allies knew that if they could hold on, they would have more soldiers and supplies than Germany could ever match.

⏳ For Germany

Germany's leaders had gambled that the U-boats would starve Britain before American soldiers could arrive. The gamble failed. Russia left the war in the winter of 1917-18, which freed German troops to move west, but time was now against Germany. It had to win in France in early 1918, before the Americans came in strength. As Germany's own soldiers ran short, its morale fell.

How significant was the US entry?

Significance means how much difference something made. Be careful with dates. In 1917 the USA made little difference to the fighting on land, because so few of its soldiers were in France. It could not stop Russia leaving the war. Britain and France still did most of the fighting, even in 1918.

But in the long run the American entry was decisive. It kept the Allies supplied with money and goods. It helped to beat the U-boats. Above all, it gave the Allies a supply of fresh soldiers that would not run out, at the moment when every other army was worn down. Germany could no longer win a long war. That is why Germany staked everything on one last attack, as you will see in the lesson The Ludendorff Spring Offensive, 1918.

Common mistakes

Do not write that American soldiers poured into the trenches in April 1917. A large army took more than a year to raise, train and ship. Do not call the USA one of the Allies in a treaty sense either: it was an Associated Power. And do not give the Zimmermann Telegram as the only reason for war. The U-boats mattered more.

Exam-style question

Describe TWO features of EITHER the Zimmermann Telegram (1917) OR the help the USA gave to the Allies in the years 1917-18. [6 marks]

Model answer

I have chosen the help the USA gave to the Allies in the years 1917-18.

One feature was money and supplies. By early 1917 Britain was close to running out of money to pay for American goods. After April 1917 the American government lent the Allies about 7 billion dollars, so food, steel, oil and weapons kept crossing the Atlantic. American destroyers also helped to guard the convoys that carried them.

A second feature was fresh soldiers, who arrived slowly at first. The regular army had only about 130,000 men in 1917, so a draft was used to call up about 2.8 million. Under General Pershing the first troops landed in France in June 1917. There were about 300,000 by March 1918 and about 2 million by November 1918.

What lifts this to the top level: two separate features, each backed by precise facts such as figures, dates and names, with no time spent on a story or an argument.

Exam tip

A features question asks what something was like, not why it happened or how important it was. For the American help, start each paragraph with 'One feature was...' and 'A second feature was...', then add two facts to each. Remember that one feature alone can score no more than 3 marks. For more help, see the Exam Skills lesson Paper 2 Section A Question (a): Describe Two Features.

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