Ferdinand Mount

According to Richard Clarke, the former White House counterterrorism chief, Bush was so obsessed with Iraq that he failed to take action against Osama Bin Laden despite repeated warnings from his intelligence experts.

For all its terrible faults, in one sense America is still the last, best hope of mankind, because it spells out so vividly the kind of happiness that most people actually want, regardless of what they are told they ought to want.

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.