Continues ad infinitum at NASA Watch, with the usual illogic from the usual suspects. This is a good analogy:

SLS is like Columbus postponing his voyages to try to build the world’s largest ship, using all the funds available to him for many years to do so. Instead of outfitting three modestly-sized ships with the crew and provisions to set out as soon as he can, Columbus spends many years to build an enormous ship. Meanwhile, no exploration is done. And Columbus makes sure the shipbuilding employs lots of people in key cities in Spain for political reasons, instead of designing the ship as efficiently as possible. In the end, the English beat Columbus to the New World because by the time Columbus finishes his ship, he can’t afford the crew or provisions for it, and the costs of simply maintaining the ship while it sits in its harbor are too high.

It reminds me of the story of Don Miguel de Grifo.

This is another good analogy:

Building SLS is like re-creating Saturn V without doing the rest of the Apollo program at the same time. It would result in SLS being cancelled, just as Saturn V was, for cost reasons, but without ever flying anything useful, because we weren’t doing another Apollo at the same time.

The only programs that could possibly use SLS would be hugely expensive and take a long time to develop. So if we finished SLS without working on the programs that would use SLS at the same time, we’d end up with a hugely expensive SLS draining money for many years before the payloads could possibly be ready, even if by some miracle all that huge amount of money appeared from somewhere (the Apollo program budgets were far greater, as a share of GDP, than NASA’s current budgets).

But some people just can’t get it. I can understand why rent-seeking senators want to fund this jobs program, but I don’t understand why any sensible space enthusiast does. But then, I guess that question answers itself, doesn’t it?