How did the lend-lease act and the atlantic charter change u. s. involvement in world war ii?

The Lend-Lease Act and the Atlantic Charter Act ended the "pretension" of US neutrality in the face of war.

Explanation:

Lend-Lease was the program through which the United States of America provided on loan to the United Kingdom, the Soviet Union, China, Free France and other allied nations, arms and other supplies, between 1941 and 1945.  The program was signed into law on March 11, 1941, a year and a half after the outbreak of World War II in Europe, but nine months before the US entered the war in December 1941. Formally entitled "An Act to Promote even more the United States Defense, "the law ended the "pretension" of neutrality of the United States.  A total of $ 50.1 billion worth of supplies were sent: $ 31.4 billion to Britain, $ 11.3 billion to the Soviet Union, $ 3.2 billion to France, and $ $ 1.6 billion for China. Under the terms of the agreement, the material could be used by these nations without payment until the time of their return or destruction. After the program closure date, material that had not been destroyed was sold to Britain at a discount as long-term loans from the United States. The Atlantic Charter was the first relevant document that preceded the United Nations. It resulted from the meeting of US President Franklin D. Roosevelt with British Prime Minister Winston Churchill in August 1941 during the difficult relations that permeated World War II. It was approved by the statesmen on August 14, 1941.