One of my many important rules regarding the Left:

They are never talking to you, they are only talking to themselves.

They literally do not even know who you are. You are outside of their moral universe, and well below consideration beyond mere invented caricature. Because they already pushed you outside of their moral framework, they did not take any mental effort to define you, besides being the enemy. As such, they literally do not know anything about you or what you believe.

That is the person you are arguing with, and why they sometimes get completely stunned when trying to debate someone on the right, even when that rightist has no training in debate or rhetoric.

It actually reminds me of some things I used to encounter as an atheist regarding Christians. If you were dealing with a Christian who understood morality to simply be Divine Command Theory (anything said by God is always good, even if it inherently and objectively evil because it is said by God), they literally do not think you are capable of ethics or morals. They can't even imagine how it is possible for you to make an ethical decision, without pre-supposing an order from God.