Do you have any sources that say it is "illegal" to discuss politics? Most of the news on TV discusses the candidates these days. I have never heard about it not being legal to talk about political issues in the United States. In fact, it would be unconstitutional if that was the case.
If you think it is illegal for kids to talk about it, that is not correct either. As long as you do it anonymously (not giving your real name), it is fine.