Could nanotechnology, genetic engineering and quantum computers could represent a threat to Mankind, as Bill Joy, the former Sun executive, warned in 2000 with his "Why the future doesn't need us"?

The world (and the universe) is full of mortal threats. Technology is the source of some of those threats -- but it has also protected us from others. I believe that technology itself is life's surest response to the ongoing risks.

Right now the Pentagon is employing 5,000 robots in Iraq, patrolling cities, disarming explosives or making reconnaissance flights. The next step is allowing them to carry weapons. Does this lead to a "Terminator" scenario?

That's conceivable, though not a reason for turning away from robotics in general. Old-fashioned thermonuclear world war and some types of biowarfare are much simpler, more likely, and probably more deadly than the "Terminator" scenario.

You set the plot of your last novel, "Rainbows End," in 2025. It's a world where people Google all the time, everywhere, using wearable computers, and omnipresent sensors. Do you think this is a plausible future?

It was about the most plausible (non-catastrophic) 2025 scenario that I could think of.

It is a little scary, isn't it? Is this the great conspiracy against human freedom?

Before the personal computer, most people thought computers were the great enemy of freedom. When the PC came along, many people realized that millions of computers in the hands of citizens were a defence against tyranny. Now in the new millennium, we see how governments can use networks for overarching surveillance and enforcement; that is scary.

But one of the ideas I am trying to get at with "Rainbows End" is the possibility that government abuse may turn out to be irrelevant: As technology becomes more important, there governments need to provide the illusion of freedom for the millions of people who must be happy and creative in order for the economy to succeed. Altogether, these people are more diverse and resourceful (and even more coordinated!) than any government. Online databases, computer networks, and social networks give this trend an enormous boost. In the end, that "illusion of freedom" may have to be more like the real thing than has ever been true in history. With the Internet, the people may achieve a new kind of populism, powered by deep knowledge, self-interest so broad as to reasonably be called tolerance, and an automatic, preternatural vigilance.