I doubt global warming will ever be a primary political issue. By that I mean, we'll see lots of policies pitched like this: "Policy X will solve Problem Y ... and will also help fight global warming." But "Policy X will fight global warming" will never be enough, on its own.
He reasons that:
While voters claim to be concerned about global warming, it takes almost nothing to knock it back among their priorities. They're concerned, sure, but they don't want higher gas prices, or any new taxes, or any new government bureaucracies, or any lost jobs, or any, you know ... cost.
Perhaps Al Gore, the Sierra Club, etc. will prove him wrong over the next couple of years and a powerful grassroots movement built specifically around the issue of global warming will emerge. Who would have expected grassroots political movements to have peacefully overthrown the Soviet empire? Anything can happen.