There seems like a bit of talking past each-other in this discussion. If the question is whether there's a threat of resurgent 1930s-style fascism, I don't think that's a serious issue in the US at the moment. The supporters of that are mostly white trash people and NEETs who aren't taken seriously.
That's who the Antifa are attacking. I don't see or hear of them attacking anyone else. They go after the easiest and most vulnerable targets and think that they're doing something very brave and noble.
If the question is the threat of a racialist and lite-authoritarian politics within an otherwise liberal framework akin to Viktor Orban's in Hungary though, the power of Steve Bannon in the Trump campaign and his early administration shows that is actually a strong current in the American body politic, as does the growing clout of "alt-lite" organs like Infowars, Freedomain Radio/Stefan Molyneux, and (formerly Bannon-owned) Breitbart. That isn't technically fascism since it's not advocating suspension of liberal democracy, it's more just broadly under the umbrella of "hard right authoritarianism," but it is a current that shares enough things in common with fascism that many people don't notice a difference. The DNVP, who essentially were it in 1930s Germany, allied with the Nazis before they were liquidated.
A lot of what we're seeing today appears to have been derived and influenced from various sources. For one, there was a strong anti-government, conspiratorial mindset fostered and encouraged during the 1960s (largely from liberal/leftist sources), and this mentality has carried over to the present day. Cynicism regarding the government has been very strong in the political culture, from both left and right.
Another issue is the economy. One key difference between the present day and the 1950s/60s is that back then, the economy was improving and reaching its peak, while today, the economy is mostly stagnant and many see America as a once-great power in decline.
One should also consider the day-to-day struggles that a lot of people have to face. Some people have to work two or three jobs just to keep a roof over their heads and feed their families. People often dismiss them as ignorant and clueless, but the one thing they're certain to know is how much their paychecks are, what they can buy, and what they have to spend.
They may not know much about the inner-workings of government, but they do know how much they're paying in taxes. They look around their communities and see nothing to show for it - other than roads strewn with potholes and city parks full of trash (because of all the budget cuts and "hard times" governments claim to be going through). They see countless vacant lots, boarded-up buildings, and shuttered factories as living reminders that things were once better in America.
They have to deal with endless bureaucracy where they take a number and wait in line. They have to wait on hold with "customer service" for an interminable period of time, all the while being told that "your call is very important to us." A lot of people may be ignorant fools, but they're not
that stupid.
You hear it from people all the time. They worry about the future. A lot of people think the country is going down the tubes - and they wonder why that is. What has happened to America? Liberals really have no answers to that question, or they try to intellectualize it so much that it ends up falling on deaf ears.
This is why a lot of people end up gravitating to alternative sources of information - such as you mentioned with Infowars, Breitbart, etc.
The only real way to counter this is by demanding greater openness and transparency in the government and other mechanisms of societal influence. Truth can be a powerful weapon, but in a society filled with deep, dark secrets, classified information, and a culture where "no snitching" is the overriding rule - few people actually want to go on record. It's the culture of silence and secrecy which breeds all this conspiratorial thinking.
I don't believe Antifa actually helps though, because it makes Bannon's co-ideologues look like victims. What the average person sees is one side being violent and not letting the other side talk, a lopsided image shattered only periodically by acts of far-right violence like Charlottesville. In general, that seems to me like the reason why the far-right plays the victim so much: for gaining sympathizers, it works, because they have examples to point to handed on a platter by the far-left.
This is true. They attack those who seem the most vulnerable and easy to attack - and from a certain standpoint, it appears more like bullying the weak - and not quite so noble or brave as they would like others to think.
This isn't like the 1950s and 60s where they might have been going up against Bull Connor and the Birmingham Police Department. They're not taking on any "Invisible Empire." Things are different nowadays. Since those times, we've seen an escalation in the war on drugs, which has given the state and law enforcement broad powers. We've seen huge crime waves in the cities, which have somewhat subsided since the 1990s but still active in public memory.
We've had 9/11, which also made an indelible mark on the public consciousness and their perceptions of America and the outside world today. That led to the Patriot Act and the creation of the Department of Homeland Security, which some people decried as bordering on authoritarianism and fascism. We've seen the militarization of police forces and a wider expansion of the security/surveillance state. We have a lot of prisons and one of the highest incarceration rates in the world. All of this had been going on long before Bannon or Trump came on the scene, and I seriously doubt that any of the white trash or NEETs had much to do with the creation and implementation of the national security state we've been living under for quite some time now.
While the Antifa have been distracting themselves chasing rats hiding in the corner, an entire quasi-fascist society has risen up around them, and yet they don't realize it. They might be noticing it now, but they seem to believe that it all has to do with Trump. I've noticed in all of these endless discussions about Trump that most of the current liberal crowd are unable to connect the dots and see the progression of events and influences which brought us to this point. It makes me wonder if they've become fossilized or perhaps still stuck in the 1960s. Or maybe they just sold out and their position is entirely based on pragmatic self-interest and cynicism.
It seems clear to me that giving rabid right-wing populists who play on peoples' emotions a platform to speak unfettered (i.e. not a debate where the opposition can speak as well) does help them spread and damages reasoned public discourse, which is why I have no objection to private organizations like YouTube cleaning up their output. That also seems to look dramatically different to the average person from violent unprovoked assault or shouting people down. I think you can notice the difference by just observing the majority opinion in the Alex Jones YouTube drama thread compared to any Antifa one.
The best way to fight an idea is with another idea. But that's where a lot of liberals fall short, since they've run out of ideas. At one time, they thought they were the "best and the brightest" with new, progressive ideas to change society, but they're really not what they used to be.