Thus Spake...

The concept of military necessity is seductively broad, and has a dangerous plasticity. Because they invariably have the visage of overriding importance, there is always a temptation to invoke security "necessities" to justify an encroachment upon civil liberties. For that reason, the military-security argument must be approached with a healthy skepticism.

--Justice William Brennan, Brown v. Glines, 444 US 348 (1980)