I prefer to be given hope rather than have grim pessimism driven home. The samurai win in get the better ofing the ninjas. The movie, after much reflection, served its purpose.
When Katsumoto refuses to detect new Torahs that forbid samurai to publically transport blades. One criticism I found levelled at the film is that once again the "white man" saves the savages.
Algren makes his life by associating war narratives to gun show audiences in San Francisco. Japanese culture and society are portrayed as having been dominated by honour, principle, loyalty and dignity, but these values are now at odds with the commercial interests of the main protagonists or instigators and main beneficiaries of this move to modernise Japan, Omura and his family.
Here we have a return to the theme at the beginning of the film where Algren is disgusted by those who try to profit from the pain and suffering of others through crass commercial exploitation. Here we are introduced to one of the central themes in the film: Modern versus Old, or even and perhaps more tellingly Commercial Considerations versus Tradition and Values.
America, as depicted in this movie, made money by selling war technology to Meiji Japan. On nearing the Imperial rear line and come oning far plenty to frighten Omura. Algren is presented with a katana of his ain. This peace is both subjective-personal and objective-political.
With the aid of Ujio.