During the time of 1930’s, US always stayed away from getting involved in European affairs. Considering this, the congress passed 3 acts of neutrality between 193-37. This law meant that US will not get itself involved in issues happening outside of USA. But the issues taking place in the world created a doubt of whether US would still follow those policies if a war ever broke out.
Amendment of neutrality act
After Germany invaded Poland in September 1939, a war started between England and Germany, which put a lot of tension on US. But due to cultural and ancestral similarity between US and England Roosevelt decided to help England and France by changing the neutrality act which enable them to buy arms from US on a cash and carry basis. This was done to help allies defeat the axis.
Panama declaration of Oct 1939
After the war started, a conference was held at Panama to keep the war out of USA. USA warned the warships of countries at war to be out of neutrality zone. But the declaration was not accepted by the war nations as it limited their power.
The Act of Havana
Another Act was passed in 1940, was called the act of Havana, it stopped any transfer of any European colony in America to non-Americans. In August 1940, USA signed Ogdensburg agreement with Canada for the joint defence of both the countries.
After the German invasion of many countries and the fall of France, US realised the importance of the situation and had to be ready for an attack any time. To improve the defences, in September 1940, the congress passed a conscription Act worth $13000000000, which would be allocated for the defence purpose of the US. So new taxes were levied to meet these expenses.
In September 1940, the congress passed the Selective Service Act, which required the registration of all men between 21 and 35years old for training of one year. Later those laws were modified which made the age category to be 18 to 45 years and training period to be 18months.
Presidential election of 1940
November 1940, Roosevelt was once again elected as the president of the USA. After the election Roosevelt adopted more war precautions. This was due to the fall of France and the increasing pressure on Britain. Therefore, US took actions to assist Great Britain though not involving itself in the war.
Lend-Lease Act of March 1941
USA asked for the support of enemies of Hitler. This resulted in passing of the Lend-Lease Act in March 1941. This act helped US supply arms to its allies. Huge quantities of goods were sent to Britain. The act was described as a declaration of economic war and soon US and Germany were involved in armed conflict. To ensure the supplies reach safe, the US acquired Greenland and Iceland to help supply goods. In September 1941, a brush between a US destroyer ship and German submarines sparked the American navel fight in World War 2. More clashes happened and a formal war was declared a little later.