The right to free speech in the First Amendment goes to content, not to venue. You have the right to say what you want, so long as your speech doesn't endanger someone else, you do NOT have the right to speak any place that you want. You have no right to say whatever you want on Facebook unless Perhaps your name is Zukerberg.

Your point about the civic duties we all owe as citizens is hugely important, and sadly unenforceable. As citizens we have the civic duty to assume the patriotism of our fellow citizens. While the right pioneered the practice of calling the left traitors who hated our country, this delinquency has spread across the ideological spectrum. We can only rebuild this basic pillar of democracy with our own behavior, which is the only behavior we can control.