I don't understand how is it possible lefties still don't get this simple concept?

The simplest and fastest way to recruit for your enemies is to go on a violent protest against them. Because, it demonstrates two simple factors.
1) Your position is not compatible with civilized society. It leads to violence against political oposition, that democracy was designed to eliminate.
2) You name your antithesis. Something, that by definition must be better then you, and is already having an effect on your lifes.

'It worked with Milo, It worked with Filip Turek. It is just that simple.

@LukeAlmighty
So here's the thing... sure leftie violence can backfire and end up increasing support for the right. But:
1) the backfire is not actually guaranteed and it takes a long time to grow,
2) far more people have proved themselves to be perfectly content to bend over backwards to the violent mobs, and support whatever terrorist demands lefties make, thinking they'll be left alone if they just follow along. It worked for Hitler, and it's working for them too. During the BLM/Antifa riots, how many store fronts were more than happy to put up signs showing BLM support just so they got spared of the looting? Normies were more than happy to give political power to people who, as you say, are incompatible with civilized society, just so they get spared of an immediate danger from a violent person right up in their face.

@alyx
Yes, obviously people will bend in the moment to not get killed. I don't think that's the point though. The point is, that people made to bend as well as people watching will remember, that it must never happen again.

@LukeAlmighty But the ones that bend don't remember. And they continue bending at every occasion for a long time. US is more than a decade since this political violence started, and normies still haven't taken a clear stance against it.
Again, people forget that this was Hitler's playbook too, with his brown shirts. This shit isn't new. It's a tactic that has been proven to work to gain political power fast.

The potential for a backlash does exist, but it takes far longer to manifest, to grow, to form a political movement, and strike back via democratic or non-violent means.
But if the ones using violence, use their gained political power to quickly infiltrate and reform power structures in their favor (with something like establishing DEI departments in every organization for example), you have the potential to prevent the opposition from being able to grow a movement and gain a foothold to any political power of it's own.

This is why the left has been using violence, and why it will continue to do so. Because it still has enough influence to trick normies into believing things like DEI are good and will solve the "social injustices" that drive BLM/Antifa to create chaos in the first place. And then they can use DEI to suppress the opposition that would revolt against their use of violence.

Hitler did this. Soviets did this. Mao did this to a ridiculous level. Steamroll radical governmental changes with the help of violence so that before the backlash has time to wake up and realize what's happening your new power structures effectively make opposition illegal.

This is what pisses me off about how EVERYONE has learned the wrong lesson after WW2/Nazi Germany. All that Europe and US paid attention to was "don't be racist", instead of learning to recognize dirty tactics such as this kind of political violence and riots.

People all over the world should have learned to recognize these signs, and nip it in the bud, with drastic measures if necessary, on day 1. There should have been MILLIONS of Kyle Rittenhouses, armed and ready at EVERY BLM/Antifa riot, with FULL societal approval and not a single tear being shed for casualties among the rioters.
Instead, all everyone cares about is "don't be racist", which just gave more political ammunition to the side that decided to adopt this yet another dirty political weapon.

@alyx
I agree with you, but Trump is in office.

That is why I am pissed off at the left. Because I am a libertarian. I do not want the same things that Trump does. I am not a conservative, and I do have nothing in common with them. Yet, somehow when these people were offered a choice between cutting all the anti-civilization shit before an insane nationalist takes the power, or doubling down, they chose to tripple down instead. And they still believe, that even now, they lost, because they didn't push hard enough the first 3 times.

@LukeAlmighty Trump is in office, but even so, the left still has plenty of power and influence. Much of which was gained with the help of such dirty tactics. Unless Trump obliterates them (which I doubt he'll manage to do), from their perspective political violence works. It has rewarded them with power, that they've still managed to hold onto even now. Hollywood, mainstream news media, universities, most big IT companies, and other multinational companies. So again, unless Trump destroys them completely, they have every reason to believe that political violence can help them hold onto power, and increase their power in preparation for 2028.

I sympathize with libertarian ideas, but as long as sociopaths and psychopaths exist in the world, I don't believe libertarianism could be fully stable long term. Not sure yet what approach is best. The only thing I'm decently convinced of is that a nation does need a decent amount of patriotism/nationalism. But what you combine that with can make a drastic difference in the end result.