Part of what makes it hard to describe is that it's many different things, in different places. It was an economic structure, a political ideology, and formed from multiple cultures, changing it. So forgive if this seems a bit scatterbrained.

Fascism was always touted as a "third way", something better than either capitalism or communism. It was a mixed system, where there were private companies but their directors of important companies (Volkswagen, and I think messerschmitt too for example) were appointed by the Party. This is something I can't really see Trump doing.

It also rejects conservatism in a way we haven't seen here. It wasn't calling back to the recent past as a better time, it was calling back centuries to the pre modern world. It wasn't a return to the monarchy, it was liberal in that sense.

It also is inherently an ideology of violence. It rejects the idea that violence is an inherently negative act, and essentially that might makes right. The brown shirts are a great example of this. They were a paramilitary force that acted as street enforcement in the early years of the Party. This one is probably a bit more debatable, but we haven't seen overt violence against protestors or the legitimization of the Proud Boys et al. Yet.

There also hasn't been the romanticization of the symbolism yet. The fascists were obsessed with the appearance of continuing the Roman empire (because it still gives off an air of authority). America has the flag obsession, but it's nowhere near the same level of grandeur or obsession.

Now, you could very reasonably point to the jingoistic nationalism (see Trump and Greenland or Panama) as a way they are very similar. There are many examples of other ways too, the very lebensraum-adjacent way they talk of the need for minerals and expansion. There's the usage of an 'other' (migrants in our case) who are weak scum who don't deserve to be here while simultaneously being ingenious at 'stealing our jobs' or 'illegally voting' or 'stealing welfare/Social Security/Medicaid'. There is also the way that they are attempting to concentrate power solely in the executive branch. Or you could also point to the way that this administration is coopting existing government institutions for their own endeavors, rather than the institution's purpose.

But the issue is that no one is able to agree on what fascism is. Every single historian you read will have a different definition of what fascism is. Some may vary a lot, some a little.

Ultimately, I come down on the side of it being an ideology that is specific to the time and place it was born, mid 20th century Europe. By including Trump in fascism, I feel like it gives him an easy out - 'Look at what they call me, I don't do X, Y or Z, they're biased and therefore don't listen to a word they say', even if the points are good that word is too emotionally charged to have much meaningful impact.

I just think we don't have a good word for that this new authoritarian ideology is. It's a judgment call imo.

But just because he's not technically fascist doesn't mean that he's anything other than an jingoistic, authoritarian asshole who has no empathy. He doesn't deserve the presidency irrespective of what word we use, we don't need to call him a fascist to resist.