We have involuntary registration of various violent offenders for several decades now. Some offenders like sexual offenders actually have to go and make it known to all of their neighbors that they are a sexual offender. However I have yet to see it degenerate to people having to go around admitting that they voted for Bush. Slippery slopes are only as slipper as people want then to be. Society knows very well where to draw the line usually if it didn't it wouldn't function, you might not like where it draws it but it's not up to you to decide that on your own anyhow.