Spin by Robert Charles Wilson Page B

done, no one seemed to know what it was. And any clearly retaliatory action—like the one the Chinese had proposed—would have been prohibitively dangerous.
    Perihelion was pushing a radically different approach.
    “The governing metaphor,” Jase said, “isn’t combat. It’s judo. Using a bigger opponent’s weight and momentum against him. That’s what we want to do with the Spin.”
    He told me this laconically while he cut up his grilled steak with surgical attention. We ate in the kitchen with the back door open. A huge bumblebee, so fat and yellow it looked like an airborne knot of woolen threads, bumped against the bug screen.
    “Try to think about the Spin,” he said, “as an opportunity rather than an assault.”
    “An opportunity to do what? Die prematurely?”
    “An opportunity to use time for our own ends, in a way we never could before.”
    “Isn’t time what they took away from us?”
    “On the contrary. Outside our little terrestrial bubble we have millions of years to play with. And we have a tool that works extremely reliably over exactly those spans of time.”
    “Tool,” I said, bewildered, while he speared another cube of beef. The meal was straight to the point. A steak on a plate, bottle of beer on the side. No frills, barring the three-bean salad, of which he took a modest helping.
    “Yes, a tool, the obvious one: evolution.”
    “Evolution.”
    “We can’t have this talk, Tyler, if you just repeat everything back to me.”
    “Okay, well, evolution as a tool… I still don’t see how we can evolve sufficiently in thirty or forty years to make a difference.”
    “Not
us
, for god’s sake, and certainly not in thirty or forty years. I’m talking about simple forms of life. I’m talking about eons. I’m talking about Mars.”
    “Mars.” Oops.
    “Don’t be obtuse. Think about it.”
    Mars was a functionally dead planet, even if it may once have possessed the primitive precursors to life. Outside the Spin bubble, Mars had been “evolving” for millions of years since the October Event, warmed by the expanding sun. It was still, according to the latest orbital photographs, a dead, dry planet. If it had possessed simple life and a supportive climate it could have become, I guessed, a lush green jungle by now. But it didn’t and it wasn’t.
    “People used to talk about terraforming,” Jason said. “Remember those speculative novels you used to read?”
    “I still read them, Jase.”
    “More power to you. How would you go about terraforming Mars?”
    “Try to get enough greenhouse gases into the atmosphere to warm it up. Release its frozen water. Seed it with simple organisms. But even with the most optimistic assumptions, that would take—”
    He smiled.
    I said, “You’re kidding me.”
    “No.” The smile went away. “Not at all. No, this is quite serious.”
    “How would you even begin—?”
    “We would begin with a series of synchronized launches containing payloads of engineered bacteria. Simple ion engines and a slow glide to Mars. Mostly controlled crashes, survivable for unicells, and a few larger payloads with bunker-buster warheads to deliver the same organisms below the surface of the planet where we suspect the presence of buried water. Hedge our bets with multiple launches and a whole spectrum of candidate organisms. The idea is to get enough organic action going to loosen up the carbon locked into the crust and respirate it into the atmosphere. Give it a few million years—months, our time—then survey the planet again. If it’s a warmer place with a denser atmosphere and maybe a few ponds of semiliquid water we do the cycle again, this time with multicelled plants engineered for the environment. Which puts some oxygen into the air and maybe cranks up the atmospheric pressure another couple of millibars. Repeat as necessary. Add more millions of years and stir. In a reasonable time—the way our clocks measure time—you might be able to cook up