If you attempt to intervene in a hostile situation, always have a gun at hand and be ready to fire it. In the case of the sexual assault, the rapists should have been immediately shot. In the first case, the man getting out of the car in perfect synchronization with the comment should have been immediately perceived as a threat, to which he should draw his gun; if the man continues to advance towards the gun holder or makes sudden movements, he should be shot. An additional precaution should be to wear as much body armor as you can (good general advice to anyone, even if you live in an allegedly “safe” area).
Defending others is a good general principle to practice (and if you can intervene without danger to yourself, you have a moral obligation to), but I would not extend it to people who can be identified as Leftists with 100% certainty. If I don’t think I could get a person to renounce their liberalism by helping them, I would not personally help them.
I hold doors open for the disabled, as well as people holding lots of groceries (unless they are confirmed liberals). If you are able to open the door yourself, you can do so yourself; holding the door for the able-bodied encourages the entitlement mentality.
All these years, I've been an enabler...
I hold the door for men or women - it's basic courtesy. I'll flip your absurd statement and and say those that don't extend common courtesy to others hasten the slide of our society into the abyss.