On this segment of Industry Focus: Energy, The Motley Fool's Nick Sciple and Fool.com contributor Lou Whiteman discuss the appeal of using space-based lasers for missile defense, and the technical challenges that go along with it. There are also ethical issues to be considered.

A full transcript follows the video.

This video was recorded on Jan. 31, 2019.

Nick Sciple: Another development we're seeing, though, is that over the longer-term, maybe we don't have to have a rocket, we may be able to use a directed-energy or a laser or something like that to intercept it. You get the advantage of, it travels at the speed of light. For these hypersonic, extremely fast weapons, it doesn't matter because you're never going to go faster than the light that we're shooting at that.

Can you talk about the challenges behind that program, both in space, of course, but also a ground-based missile intercept program that operates through a laser delivery?

Lou Whiteman: You're absolutely right. In theory, laser is the solution to a lot of our problems. It's easier to rearm in space, it's much faster. Again, when you're talking about a matter of seconds to get something fired, a laser makes a lot of sense. Unfortunately, easier said than done. If you have the laser in space, it needs a certain amount of energy just to penetrate our atmosphere. If you think about the energy that's already required just to do damage and halt an ICBM, you're talking about an incredibly powerful laser up in space. Are we capable of it? Yes. But the battery requirements, the recharging requirements, it's going to be a huge satellite that, in theory, could be pretty easily targeted itself. The laser helps with timing, but it doesn't mean we just stick one over the United States and that's fine. You may not need thousands, but you need hundreds of very, very expensive, very complex, and somewhat vulnerable satellites out there to make it work.

It's not reasonable that we're going to see this now. Again, technically, is it possible? Yes. Could we demonstrate it? Yes. But, are we going to build a fleet of these that could effectively protect our country anytime soon? That's hard to imagine. At best, from the contractor's perspective, this is intriguing enough that there's going to be R&D. The Defense Department is spreading money around quite a bit in relatively modest amounts just to work on advancing this. But it's an incredibly difficult problem to solve with the battery capacity, the recharging, and just dealing with things in space. We're not ready to solve it. It's still in the drawing board.

Sciple: Definitely something to watch as we look out over the long-term. We talked last week about batteries. This is another instance where battery technology is going to be really important, even touching the defense space.

Whiteman: The bigger-picture thing, too, that we have to consider as we're doing this, is there is a moral dilemma of what we're talking about here -- pretty automated systems in space with lethal weapons. By default, we have to let them work on their own. There is not time for a human to analyze the data, say, "Yes, this indeed a launch, fire." We have got to get these systems to a point where they can reliably say, "Yes, this an ICBM with dangerous intentions, and it needs to be taken out." There's a real risk that if something goes wrong, there's a laser or a rocket up in space that's going to be launching an attack on a foreign nation when they're just putting up a weather satellite. Hopefully that wouldn't happen. That's an extreme example. But there's a lot to grapple with as we do this.

Like I said, this is very neat. It's going to be R&D. It's going to be talked about for years to come. I would not invest on this now, though, thinking that this is going to happen within a reasonable time period.

Sciple: Yeah. Everybody knows about the hype cycle. When it comes to these directed-energy and laser technologies, it's very exciting, the promise, what we can see in the future; but the capabilities to actually carry that out at scale, we're going to need to see some additional R&D before those can really move up.

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