Mbiker, 
Thanks. What the ranger said is somewhat accurate in that when a call comes, a response from the agency is required. That being said, on an individual level, no one in any agency is "forced" to go on any mission that they feel bears an unacceptable risk. The military may have a different rubric for risk, but agencies such as the NPS have a very strict risk mitigation protocol. My greater point was that the men and women who work as professional rescuers understand these risks and they sign up willfully as part of the job. In your case the ranger may have been using a bit of hyperbole to head off what they felt was a potential unnecessary risk- to themselves yes- but also to you. (And not knowing you, I'm not saying their assessment was right or wrong). I work in SAR and know many in these agencies.
I totally agree with your final sentence. I wasn't trying to be nasty, but the poster above made a grossly false statement (while being condescending) which needed to be corrected.