Social movement is a theme quite prized by French cinema. It is however generally depicted in an analytic way, aimed to explain, rationalize.
Here, we are shown, or even pushed into the events, from the inside. And what we are shown is a social conflict, and a big one: an industrial site, employing 1000+ people, is supposed to be shut down, by decision of the parent company. The employees refuses to just lose their jobs like that, only 2 years after firsts sacrifices in order to keep the site working on top of that.
This conflict, between men and and the power of money and finance, is shown in all its rudeness.
In such situation, it is indeed a war - with your lives as they are at stakes (as proclaimed by one of the leaders, an important part may never have the chance to work again). But fought not by soldiers, leading to difficulties to keep a straight line, a united front or even a cool head.
I think the director did an impressive job to put the spectator into the action. We are thus forced to think: what we would do at their place? Would we accept the market rules? Go for the money? Fight for work and justice?
It is indeed so easy to judge from afar and the movie manages to break that distance.
The final part may be too much but this movies draws a ferocious portrait of social conflit, our society, its contradictions and its dead ends.