As much as I hate to admit it, quite often the most lucid, compelling case you can make for your positions is silence. The simple fact is, many people have NO intention of changing their views, and anything you say can and will be construed in a negative way.
Some of these people will never wake up, ever, in their entire lives. This happens often, although it takes a great deal of determination to keep out all contrary inputs when you are defending the indefensible.
Others, it takes time and events that are unforeseeable, and certainly uncontrollable. There may, some day, come a time when they will listen.