Houston, we have a problem: Nasa will struggle when shuttle retires, says boss, Guardian
"It is more than a matter of pride. Griffin likens the space station to a miniature Antarctic research base, which needs a regular supply of food and water, which suffers technical glitches, and needs to have its staff rotated on a regular basis for their sanity if nothing else. Both the US and Russian space agencies agree that at a minimum, it needs two independent supply chains - read rockets - to ensure the safety of the station and those on board. Nasa's push for the moon and Mars will leave just one. "Anyone who doesn't understand why that is a problem, from my perspective, just hasn't done enough real things in their life."
Editor's note: I agree Mike. So why is NASA creating the gap in the first place? Why has the gap grown during your tenure?