In a nutshell, the Act gives FEMA the responsibility for coordinating government-wide efforts. The Federal Response Plan includes contributions from 28 federal agencies and non-governmental organizations. This also gives latitude to the “unity chain of command” spoken of by Pence in his speech to the troops on Jan 16, 2021.
The word “unity” is not a common term as typically it is just referred to as Chain of Command. That subtle difference means that in the instance of an unforeseen event, troops should work together with other operators, law enforcement, fire and rescue, security in the immediate AO (area of operation) rather than follow their Chain of Command. Let’s not forget about the recent letter from the Joint Chiefs in which they threaten sedition to the troops if they choose not to follow the Chain of Command. Coincidence?
https://www.monkeywerxus.com/blog/the-sicilian-defense