The Neutrality Acts were a series of laws passed in the United States in the 1930s, in response to the growing turmoil in Europe and Asia that was to lead to the Second World War. They were spurred by the growth in isolationism in the US following its costly involvement in World War I, and sought to ensure that the US would not become entangled again in foreign conflicts.

The legacy of the Acts is widely regarded as having been generally negative; they made no distinction between aggressor and victim, treating both equally as "belligerents", and they limited the US government's ability to aid Britain against Nazi Germany until the formal declaration of war in 1941 rendered them irrelevant.

In each case, the acts provided for the president to invoke them by finding that a state of war existed in a particular instance. This provided a loophole that President Franklin D. Roosevelt carefully exploited to ensure that US allies overseas were not unduly penalized by the acts.

Neutrality Act of 1935

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The Neutrality Act of 1935 prohibited American citizens from selling arms to belligerents in international war. It resulted from Italy's invasion of Ethiopia. However, the act did not set limits on trading in war materials (such as steel and oil).

Neutrality Act of 1936

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The Neutrality Act of 1936, passed in February of that year, sought to close the loopholes in the 1935 Act by prohibiting trade in war materials as well as loans or credits to belligerents.

Neutrality Acts of 1937

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Two Neutrality Acts were passed in 1937 (in January and May) in response to the outbreak of the Spanish Civil War - this was not covered under the early legislation, as it applied only to conflicts between nations rather than within them. Sponsored by the isolationist Republican Senator Arthur H. Vandenberg, it tightened the restrictions on US businesses and private individuals assisting belligerents, even prohibiting travel by U.S. citizens on ships of belligerents. When Japan invaded China in July 1937, starting the Sino-Japanese War (1937-1945), President Roosevelt chose not to invoke the Neutrality Acts by declining to identify the fighting as a state of war. In so doing, he ensured that China's efforts to defend itself would not be hindered by the legislation.

Neutrality Act of 1939

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The Neutrality Act of 1939 amended the earlier legislation in recognition of the imminent Nazi threat to western Europe's democracies. Although the Act permitted all belligerents to be supplied on a "cash and carry" basis, this benefitted the United Kingdom and France since they controlled the sea lanes. However, US vessels were forbidden to enter combat zones and US citizens continued to be barred from sailing on belligerent vessels. The act was amended in November 1941 to remove these restrictions following the passage of the Lend-Lease Act.

1937 in law | United States federal legislation | United States foreign relations legislation | United States federal legislation