There is a whole shelf-full of studies, going back decades, that conclude the best way to move humans beyond low Earth orbit is with a heavy-lifter like the SLS. Alternate methods—smaller launchers and in-space refueling depots, for example—fly in the face of the lessons learned with the dangerous and time-consuming process of building the ISS in orbit, and would require new technologies that will cost even more money and time. Instead, NASA has decided it wants $105 million in new funding to begin work on an asteroid-capture mission that would give a focus for near-term human exploration beyond low Earth orbit (AW&ST April 29, p. 36).
Mikulski is right. “Faltering and sputtering” now could indeed “blow the whole program.” Congress already has shielded air traffic control from sequestration. Is the U.S. space program any less important than on-time arrivals for air travelers?