The main purpose of the Safeguarding the Use of the National Guard Act, also known as the SUN Act, is to establish a system of congressional oversight for the domestic deployment and use of the National Guard. This legislation aims to ensure that there is accountability and transparency regarding how and why the National Guard is utilized within the United States. Key provisions of the Act require the President to submit a report to Congress within 15 days of deploying or using National Guard members domestically.