A red herring is an issue raised that is distinct from the issue at hand, and so, destracts us from the issue at hand. Oftentimes, the person raising a red herring will say some very agreeable things that do not actually support his/her view on the issue at hand, yet they can be effective in putting us in an "agreeable mood," and so, make us more likely to accept his/her view on the original issue. Red herrings are sometimes raised intentionally and sometimes unintentionally, but either way, it's good to be able to notice them so we can better focus on evaluating the reasons given for the actual issues that interest us.
Example #1:
Example #1: