After the world’s economy crashes in 2025 along with most of Western society, a man of peace arrives on the political scene and revives what one English journalist writes, “The new Roman Empire”, through a scattered European Union and United Nations, leading to the World’s third and final World War.

OK - the setup is a man appears on the scene and his rule leads to a war. Who is the protagonist of this story? Is it the politician?

If so, once he rises to power (this seems to be the setup), what is the character's goal?

So... the journalist is the narrator. Who is the protagonist, the person who opposes the "Beastly" system?

Yes, it's The Beast from revelations. The Beast would be this revived Roman empire that brings a resolution to the economic crash (cashless society, all stored on the human body -- hand and/or head/forehead) but then it'd start terrorising the world and all those who don't take on their system leading to the third World War with the English journalist, documenting everything as it happens so we are seeing it through his eyes almost like a documentary-style/City of God film.