Protests are only important to protesters. The rest of the country doesn't even notice them.
I beg to differ. Just because most Americans don't attend doesn't mean they aren't interested. And even if they aren't interested, they still notice on some level. It helps to shape their ideas of who has the energy, the self-confidence, etc. It may give more tuned-in people ideas of things they can say when they get into discussions. It provides examples of left-liberal arrogance and viciousness and lack of patriotism, and, we can hope, of conservative-patriotic intelligence, decency, and courage. I'm sure plenty of people were happy to see whatever coverage there was of our counter-rally. Ditto for those in the armed services and their families.
Even people who simply don't care about the issue will still notice. After all, I didn't give a rat's behind about the Natalie Holloway story. But I couldn't help hearing about it, and I now have a mental picture of it
and of how it was handled by the various participants, whether I want to or not.
I'm afraid your imagination, in other words, is a little weak here. Human psychology, and political pyschology, is more complicated than you think.