By the mid-1930s, the rise of Adolf Hitler’s Nazi Party in Germany threatened to engulf Europe into another world war. The United States, meanwhile, had taken an isolationist turn, with Americans refusing to send more young men to die on foreign battlefields. More than 100,000 U.S. troops were killed in World War I, sacrifices that many Americans believed were made in order to stuff the pockets of the U.S. arms industry.

When Hitler marched into neighboring Czechoslovakia, Austria and Poland, it prompted joint declarations of war from two of America’s closest allies, Great Britain and France. But the U.S. remained stubbornly neutral, bound by Congress not to lend aid or assistance to any “belligerents” in the European conflict.

President Franklin D. Roosevelt understood, though, that the best way to keep American troops out of World War II was to help the British and French defeat Hitler without us. That required money, munitions and equipment—foreign aid that was explicitly banned by the Neutrality Acts.

Through a series of savvy political maneuvers, FDR was able to work around the isolationists in Congress and find ways for America to contribute to the war effort long before December 7, 1941, when the Japanese attack on Pearl Harbor forced the United States off the sidelines and officially into the war.

FDR 'Bends' Neutrality Laws at the Canadian Border

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British Prime Minister Neville Chamberlain arrives in London holding the Munich Agreement signed by Germany, France, Great Britain and Italy.

Congress passed the first Neutrality Act in 1935, barring the export of “arms, ammunition, and implements of war” to any foreign nation at war. With the outbreak of the Spanish Civil War in 1936, isolationists in Congress amended the Neutrality Acts in 1937 to include even more restrictions on foreign aid and civilian involvement in overseas conflicts.

“Roosevelt didn’t like the neutrality legislation,” says Warren Kimball, an emeritus history professor at Rutgers University and author of Forged in War: Roosevelt, Churchill and the Second World War. “He saw the direction things were going in Europe and it took away his ability to act.”

In 1939, Hitler defied the 1938 Munich Agreement—which Britain and France hoped would appease Hitler’s imperialist urges—and invaded Czechoslovakia, making a wider war with France and Great Britain all but inevitable.

“From that point, Roosevelt began to gently but firmly bend the rules of neutrality,” says Kimball. “He and his people found legal ways to get weapons to the French, but it took some creativity.”

Under the Neutrality Acts, for example, war planes could not be flown out of the United States for sale to foreign governments. So the FDR administration quietly came up with a solution. They flew some World War I-era planes to the Canadian border, parked them a few feet from a border crossing, and let the Canadian authorities tow the planes over the border with ropes.

‘Cash and Carry’ Arms Sales to Britain and France

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Hundreds of shells ready for filling at a Midland munition works, circa 1939.

In 1939, Hitler invaded Poland in a direct provocation to Britain and France, who immediately declared war on Germany. FDR knew that it would take more than sneaking a few planes over the Canadian border to keep the United States out of this war, so he persuaded Congress to amend the Neutrality Acts to allow for the unrestricted sale of supplies and weapons to European allies on a “cash and carry” basis.

Cash and carry meant that foreign governments could buy American-made munitions and airplanes, but they had to pay cash and they had to transport the equipment on their own ships. American politicians didn’t want a repeat of what had happened in World War I.

“Some Americans were ‘traumatized,’ if you will, by the fact that our World War I allies had borrowed a lot of money from the U.S. to buy weapons and food, and never paid it back,” says Kimball. “And they also wanted to avoid the problem of American ships carrying war materials across the ocean. After all, the sinking of the Lusitania—a British ship carrying American passengers—was one of the events that had pulled the United States into World War I.”

Just three days after the Neutrality Act was amended to allow cash and carry sales, the British government set up the British Purchasing Commission in New York City to expedite sales of American-made munitions for immediate export to Europe.

Lend-Lease Program Opens Floodgates of U.S. War Aid

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British soldiers stack crates of TNT gunpowder in an ammo dump in the tunnel in western England. The TNT was shipped from U.S. under the Lend-Lease Act.

The British Prime Minister Winston Churchill took office in 1940 and watched with horror as the Nazis invaded and occupied France in a matter of weeks. Britain was now fighting Germany essentially on its own, and it seemed very possible that Adolf Hitler would win.

Churchill wrote FDR requesting a “loan” of 50 American naval destroyers, but Roosevelt knew that Congress would never approve it. So FDR’s attorney general came up with a creative legal workaround that allowed the president to send the ships using an executive action. In what’s known as the “destroyers-for-bases deal,” FDR traded the World War I-era destroyers in exchange for 99-year leases on some British bases in the Western Hemisphere.

By December of 1940, as the British were pounded by nightly German bombing attacks, Churchill wrote FDR again saying that “[t]he moment approaches when we shall no longer be able to pay cash for shipping and other supplies.”

With the situation increasingly dire for Britain, FDR and his treasury secretary Henry Morgenthau responded with yet another scheme called “lend-lease.” Instead of acting alone, Roosevelt tried to persuade Congress to loan war material to the British with the hope, but not the assurance, that it would be paid back. In a press conference, FDR compared it to lending a hose to a neighbor whose house is on fire. You might not get the hose back, but at least your house didn’t burn down, too.

Congress, sensing that it could be America’s last chance to stay out of the war, overcame isolationist opposition and passed the Lend-Lease Act (subtitled “An Act to Promote the Defense of the United States”) in the spring of 1941, creating the Office of Lend-Lease Administration.

As part of the debates in Congress, some Senators wanted to explicitly block the Soviet Union from receiving any Lend-Lease aid, but Kimball says that FDR’s supporters “presciently” struck that language. The allies may have never defeated Hitler without the Soviet Union, and the Soviets depended heavily on Lend-Lease aid in the form of raw metals, explosives and fuel.

Winston Churchill famously called the Lend-Lease program (not the Marshall Plan) “the most unsordid act in the whole of recorded history.”

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