Are you talking about giving the miranda to ARMED people?
Cops are allowed to kill armed hostage-takers without "trying to arrest them".
An armed person in a highly hostile/dangerous place does not enjoy the luxury of the 5th amendment which is meant for ordinary citizens who are not threatening to shoot at the USA government.
A terrorist US citizen is the same as an unstable kid with an AK47 who is hiding in his place of crime. The police would shoot him dead. And so would the USA military.
You should try arresting someone with AK, and tell me how that goes.
You'd be dead. and the world would have a bump in IQ average.