All of your examples still have a licensed ham within feet or inches of the non-licensed operators which is acceptable. However, in 2008 I think you'd be hard pressed to convince an FCC board of review or a court that you (a person) only had a ham radio to call for help on about a train wreck on a non-ham channel...especially if you weren't a licensed ham.
I think the scope of "life and death emergency" is a bit more focused than that.