Dan Webster

You lay out a plan and - say a three-year plan or a two-year plan - and say, 'This is what we can do. We can do the transportation packages, like the highway bill and the water bill, and we can do some of these other areas - a farm bill - whatever it is, we lay out a schedule, and we put that committee to work to do that.'

The historical novelist has to consider what has actually happened, while the SF writer is dealing in possibilities, but they are both in the business of imagining a world unlike our own and yet connected to it.