[ambrose]

You tell me what's so difficult about stuffing a couple of astronauts in a rocket and launching them off to Mars.

If the risk is such an overriding factor, then perhaps we can find a retired astronaut with a terminal disease who'd relish going out in a blaze of glory.

[Prime Choice]

You tell me what's so difficult about stuffing a couple of astronauts in a rocket and launching them off to Mars.

Four things:

1. Food.
2. Water.
3. Oxygen.
4. The adverse reaction of the human psyche to prolonged confinement. This phenomenon is exacerbated by an order of magnitude when confined with another soul also undergoing to same stressor.

In short, this venture is not something to be undertaken lightly. Yes, it must be undertaken, but not in a half-assed way.

The Apollo missions were a 9-day round trip on average. The Mars mission is a 3 year venture MINIMUM: six months getting there, two years staying there while waiting for Earth to complete an orbit and rendezvous with Mars again, and a six month journey back.

See http://www.windows.ucar.edu/tour/link=/mars/mars_orbit.html to appreciate the launch, rendezvous, arrival, departure, and return logistics. And that's just one small part of the whole equation here. You also have to consider living quarters, the human reaction to such confinement, and a host of things that can (and most likely will) go wrong without proper planning and execution.

One more thing: it has to be fail-safe. You can forget about a rescue mission when the Earth and Mars are at opposite ends of the Sun.

In short, there's a damned good reason why they call it "rocket science."