A tactic to remember is to stay calm and not respond with negative emotion. That's how they pull you in and drag you down to their level. Respond with facts or with responses that are dismissive in tone, such as one word replies, without actually being outright dismissive and negative.

In other instances, which are better suited for flowing conversations (or what could kind of be considered as a conversation with the unhinged left) hold a role of empathy and one of kindness. Even if it's not your thing, hold your attitude and don't get pulled in. Think of how you would approach a topic that you disagree on with one of your best friends or your favorite person in your family. Stick to your principles but don't get worked up.

Think of how the Trump supporter responded at https://www.youtube.com/watch?v=q3XgXYvMVbg Do that, only in textual form. Remember, people that you don't even know can see your social media comments, tweets, etcetera and can be swayed by them. Especially since everyone wants to belong and they'll tend to gravitate towards the nicer people. Meanwhile, your niceness will frustrate these leftists because they're not getting the reaction that they want. They are working themselves up into anger and will make themselves look like a fool.