Conducting joint operations generally involves how many broad principles?

I believe there are 12 principles.
The principles that they held after 2000 put a lot more societal factors/consideration compared to the principles that they held during the world wars era.
Those principles are: Objective , Offensive ,. Mass , Economy of Force ,Maneuver ,. Unity of Command , Security , Surprise , Simplicity , Restraint ,Perseverance , and Legitimacy 

Ongoing civil wars western roman empire finally collapsed476 c.e. romulus, the last of theroman  emperors in  the west, was overthrown by the germanic leader odoacer, who became the first barbarian to rule in rome. the order that the  roman empire  had brought towestern  europe for 1000 years was no more.