This is the slogan of a post-9/11 (and ongoing) MTA campaign that's been borrowed by the Department of Homeland Security and many other agencies around the coun

This is the slogan of a post-9/11 (and ongoing) MTA campaign that's been borrowed by the Department of Homeland Security and many other agencies around the country and the world since. I believe the original intent was mostly about reporting unattended bags that could contain bombs, not reporting your neighbor for hosting a socialist book club or whatever. Obviously it's vague and broad enough that it could be bent to more sinister purposes though.