from Ken
They and other factors cause our law enforcement folks to be excessively cautious.
That depends on the jurisdiction - dependent on how much prosecutorial and official immunity is given by law; and how judges apply that law. Reasoned discourse would require stats on civil actions brought vs prosecutors & cops, how many are successful, how prosecutions were affected by the suits, etc. I don't have stats at hand for that. If you do, present your evidence. You know I'll listen.

from Ken
I'd also submit most European and virtually all Asian agencies involved have and take more latitude in treatment of suspects and in not apprehending at the first scent of a crime.
.....
Agreed; tougher but also rather different with respect to the 'rights of the accused.'
Different systems from US (except in UK), based on judicial investigations akin to one-person grand juries with broad inquisitional powers. Also, generally in their criminal law, there is less emphasis on defects in procedure and presenting evidence - and much more emphasis on the degree of the crime and the term of punishment. Which is one reason which probably lies behind the decision to shift investigation and initial processing to foreign countries. Once a case is established in the foreign country, the FBI-DoJ can accept delivery, etc.

UK is similar to US. The differences favor / unfavor perps are probably a push; except that the UK has more EU conventions, etc. that they take seriously - and I think, make the job tougher as to terrs. David has the final call on UK issues.

from Ken
As long as you realize it is not dual track in several senses of 'not' -- and that DoD (and the CIA; NSA also to an extent...) cannot and should not do anything domestically.
My chart and explanation covers this to some extent - and the restrictions (and exceptions - "anything" is too broad under existing law, conservatively applied) to various agencies' charters re: domestic activities - has been covered in War Crimes and elsewhere. Anyway, they are well known to me and within my realization.

Hey, Subotai was a taiga forest boy. I can relate to that.