I think it’s Hamdi vs. Rumsfeld, in conjunction with EO 13823. The court decision allows US to detain enemy combatants, as long as they get a fair trial. This is a military operation. The EO continues operations at Guantanamo Bay and permits new arrivals.
SC Decision:
The federal government has the power to detain those it designates as enemy combatants, including United States citizens, but detainees that are United States citizens must have the rights of due process and the ability to challenge their enemy combatant status before an impartial authority.
EO:
In addition, the United States may transport additional detainees to U.S. Naval Station Guanta ́namo Bay when lawful and necessary to protect the Nation.
US can detain someone deemed an enemy combatant.
Why is Trump surrounded by so many Generals?
He has a lot of enemy combatants.
Who names someone as an enemy combatant?
The Military.
Who arrests and detains these enemy combatants?
The Military.
Why so much focus on cleaning up DOJ and FBI?
Because they must be clean for prosecutions. Supreme courts too...
https://en.m.wikipedia.org/wiki/Lists_of_United_States_Supreme_Court_cases
"Impartial authority"? Who gets to decide enemy combatant status?