Comment Re:Yes, for any mission (Score 2) 307
It would never be two-way for everyone. Some will die there.
By accident if nothing else.
By that definition, going to my office every day isn't necessarily a 2-way trip. Nor is getting up to use the bathroom, or going to the store for food, or going to bed. But it doesn't mean that I'm going to stop doing those things. I go planning to return, but accept some varying level of risk based on the potential benefit of making the trip. Going to bed is safer than the bathroom. Going to the bathroom is safer than going to the store. Going to the store is safer than going to Mars. But, depending on the individual and the perceived benefits, all of those adventures may be undertaken.