Reader Rebuttal - Fusion

A reader writes to me, questioning my love of fusion power:

Name one functioning fusion power plant (other than the sun), or even a prototype. Last I heard, we're still decades away from the first one.

Let's ignore that Bussard Fusion is nearly at positive yield, the Navy is on their 8th prototype of Polywell Fusion, and that a commercial plant is conceivable within 10 years.

Instead I want to focus on the core of this argument: "technology proposed does not exist, and possibly never will. Therefore, why fund research that will develop this technology?" Obviously I am not talking about warp drives or teleporters when I say this is a crummy, cynical sort of an argument. Should Benz have ignored the idea that a motor could be strapped to an axle via transmission and power people about town in an "automobile?" Because there was a day when any transport other than a horse or train seemed wildly far-fetched. And there was a day when atoms were the smallest things in the known universe. Should we have pulled funding on atomic structures, just because no one had yet proven that electrons and protons existed?

Teleportation, or faster-than-light travel, are topics I can understand cynicism because they require clear and concise violations of the laws of known physics. But right now I am writing this post near a window and that window has photons coming through it, sent here from a giant fusion reactor 8 light-minutes away, and somehow that fusion reactor is stable and continues to power the solar system. So its not like "fusion" is an impossible dream of science fiction. It's right outside, every day.
And it's not even that humans have never achieved fusion of their own. Although early nuclear weapons only achieved fission, many modern thermonuclear devices depend on fusion reactions inside their warhead for their intense destructive power.
And how often in history has a fundamental physical property/technology been first harnessed for war, and then tweaked for peace? Just think of jet engines...first developed at the end of World War II, and now innocuously used on thousands of passenger planes every day to ferry people about. But was there a time when jet engines, and planes in general, seemed impossibly far-fetched and a waste of government research dollars? Certainly. Aren't we glad that the naysayers weren't the ones with the final say?


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