It's one of those laws that sounds good, but was just rehashing previous laws and creating another stick for the law to go after people who weren't breaking previous laws. Standard think of the children shit, packaged around being able to harass enemies of the state when they can't go after them for anything else. It's pretty much unused since it's creation back during the Bush years, except to send a message. In other words, imgur and reddit have been breaking this law since they've first allowed adult content, without any repercussions. Which should tell you how much the state actually cares about underage porn.