Do you really root for him ? Maybe in the beginning of the movie but definitely not towards the end. At least for me personally. He’s definitely an anti-hero not a hero, not that anti-heroes can’t be likeable and relatable. But Day-Lewis’ character doesn’t really come across as that. At least to me personally.
Anyway, it’s too complex a movie to really root for one side against an other. This post is referring to movies with more straightforward ‘good’ and ‘bad’.
So, I mentioned the first point because "underdog" works against government, too, or organizations that aren't so explicitly business-oriented. That's the part that I think is fair to ask, and fair to attribute to Hollywood's collective ideological leanings, which again, I assume are not really controversial.
I get the OP's point... just think he used the wrong term
In terms of the OP... socialism is like, everyone is equal, nobody has more than someone else. Money or whatever.
Everyone has the same.
That's kinda how I see it anyways. Probably wrong but not getting into a political argument over it
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But, in terms of the OP...
Hollywood likes the underdog.
The underdog is the small guy. The little-person.
Oppressed, held down... held back... and the antagonist being a big corporation or conglomerate... maybe the government or a system of control that oppresses the People.
Maybe a system that lies to the People.
Soylent Green.
The Matrix.
Bourne.
They Live.
Even the original Rambo
First Blood.
The powers-that-be are either corrupt, or at least at a very basic level, they have something wrong with them.
Usually the powers-that-be also known they're in the wrong, but will do anything to hold onto their power, or maybe don't even realise it, and ignorantly stand fast in the belief they're actually in the right.
The little-guy stands against it. Stands against oppression... shows others there's a better way... and usually wins in the end.
The underdog trope... is a way of taking a relatable persona and making them the hero.
As the audience watches, they're in a world of escapism... and seeing someone who is, well, just like them, winning against a far greater and more powerful entity... or showing the oppressed that they
are oppressed, and changing the world... gives the audience a sense of warmth.
Prime example is a line from LOTR throws it straight into your face:
"Even the smallest person can change the course of the future"
"Smallest" being literal in both senses.
Tolkien wrote the Hobbits, and Hobbiton, as middle England.
Small (literally and figuratively) and unassumingly quiet people... from a place that most of the world kinda ignores or doesn't even know exists... and these people have it in them to literally change the entire world.
I used "underdog" as a means of maybe steering the convo away from any political ramifications