I do wear a button on my ID lanyard for work. The button says: Radical Militant Librarian, Defending Access, Defending Freedom, Defending Privacy.
Defending Access means that I believe in a reader's (or watcher's or listener's) right to have whatever materials he or she wants. If the library user is a child, it's NOT my job to say, "no you can't read that!" based on my own taste and sensibilities.
I can guide a child to pick what is best for her reading abilities and interests. After that, if the parents want to censor, it may grate on my nerves, but that is up to the parents. Challenged books, by the way, once the media gets the list out, fly off the shelves. Challenged and banned books will always be read in secrecy: under the covers with a flashlight, outside in some quiet place, at your friend's house--the friend with more liberal parents.
And by the way (at least in my library system), it takes a subpoena to the library director herself, to wrench the record of what you read out of our computers. And once material is returned, there's no record that you ever checked it out in the first place (unless there are fines to pay--then, once they're paid, the record disappears).
Anyway, that's one part of my job I really treasure: defending access, freedom and privacy.
That said, I regret that library cards do expire and we do require some kind of proof of who you are and where you live. We want to make sure we get information to you in a timely manner (like if you requested a book) and with email service, we'll even warn you in advance when your materials are due, so you can renew them online, in person or by phone.
And we do this for free. So, if you have a library card about to expire, please take a utility bill or your current driver's license--something that will make it easier for the underpaid clerk at the Circ desk, or the underpaid librarian at the Info desk to help you maintain your access to the best free service in the world: your public library.
By the way, Beth Thames, in the Huntsville Times wrote a lovely opinion piece on challenged books. She imagines a favorite teacher saying, "That's just nonsense," to the notion that reading and life have to be sunny.
Well, to the challengers of books, I'd like to say something stronger and much more salty. But for now, I'll just wear my button and make sure everyone who wants one, gets a card. And gets to read whatever she or he wants to read.