September 11 Attacks September 11, 2021 10:49 am US Marks 20 Years Since 9/11 Terror Attacks The U.S. marked 20 years since the terror attacks of 9/11 at ceremonies across the country. US & World Videos 1:20 Gigi Hadid wows in sweeping Met Gala look 1:52 Amanda Seyfried reveals her kids' reaction to her daring metallic Met Gala look 1:34 Nicole Kidman floored over Olivia Rodrigo's AMC ad tribute 3:45 Gabrielle Union and Dwyane Wade's daughter had cutest reaction to mom's Met Gala dress 1:12 Ariana Grande channels Glinda at 2024 Met Gala