This bill, known as the "Border Drone Threat Assessment Act," requires the Under Secretary of Defense for Intelligence and Security to conduct a comprehensive assessment of threats posed by unmanned aircraft systems (UAS) operating at or near U.S. international borders. This assessment must be completed within one year of the bill's enactment and involves consultation with various federal agencies, including the Commander of USNORTHCOM, the Director of National Intelligence, and the Administrator of the FAA. The primary goal is to understand the scope and nature of UAS activities by malign actors in these critical border regions. The threat assessment will delve into several key areas, including identifying the malign actors involved and their methods for acquiring, modifying, and utilizing UAS for malicious activities such as surveillance, attacks, or conveying contraband. It will also evaluate the U.S. government's current capabilities to detect, identify, and counter these UAS threats, assessing whether existing resources and authorities are sufficient to achieve complete air domain awareness. Furthermore, the assessment will consider the impact on privacy and civil liberties for lawful UAS operators. Following the completion of this assessment, the Under Secretary of Defense must submit a detailed report to appropriate congressional committees within 180 days. This report will summarize the findings, describe current government responsibilities and policies for addressing UAS threats, and provide an assessment of whether changes in authorities or additional resources are necessary. A subsequent briefing to Congress will ensure transparency and facilitate legislative action based on the assessment's conclusions.