I Fighter Command was a United States Army Air Forces intermediate command responsible for command and control of the fighter operations within the First Air Force during World War II. It was initially established in June 1941 as the 1st Interceptor Command to provide air defense of the Northeastern United States. Following the attack on Pearl Harbor, the command's area of responsibility extended over the entire Atlantic coast and into Canada and Iceland. As the perceived threat of attack decreased, the command's responsibnility for training units and aircrews became its primary mission. The command continued its mission until March 1946, when it was inactivated.