"Military units can train in larger blocks."—In-game description
Bushido Principles is a technology in Age of Empires III: The Asian Dynasties that can be researched at the Consulate by the Japanese if they choose Japanese Isolationism once the Colonial Age is reached. Once researched, it increases the number of units that the player can train at one time to ten.
Bushido Principles provides Japanese players with the potential to rapidly muster enormous armies. It should be noted that being a research, its effects are permanent, and thus, choosing a European ally later in the game does not negate its effects.