In recent decades, the United States has experienced significant shifts in social and cultural norms, especially regarding issues of equality and representation. One notable shift has been the increasing visibility and advocacy for LGBTQ+ rights. By the early 2000s, legal battles at both state and federal levels began to emerge, influencing public perception and policy. Understanding the key events and milestones of this movement is essential to grasp its impact in contemporary society. Which of the following milestones was most significant in the advancement of LGBTQ+ rights in the United States in the 21st century?