[yasp]

> When it comes to ballistic missile defense, “you want to get it into airborne platforms and into space,” said Evan Hunt, a former U.S. Air Force navigator who now works in business development for Raytheon’s high-energy laser products. “It’s better to look down than to shoot up.”

What about atmospheric interference? (And whatever unfortunate soul might be behind the missile assuming the laser misses.)

[saidajigumi]

This was a main focus of a huge amount of research backing Regan's "SDI" - Strategic Defense Initiative, back in the 80s. [1]

The field of wavefront adaptive optics[2] was a major civilian-side outcome of that work, with eventual impacts on human vision correction (e.g. LASIK, esp. for people w/ major astigmatism) and ground-based astronomy.

[1] https://en.wikipedia.org/wiki/Strategic_Defense_Initiative

[2] https://en.wikipedia.org/wiki/Adaptive_optics#Wavefront_sens...

[cosmie]

> with eventual impacts on human vision correction (e.g. LASIK, esp. for people w/ major astigmatism)

That's really neat! I'm a beneficiary of this - with both nearsightedness and major astigmatism, I was told by the ophthalmologist that did my intake for LASIK that there was a non-trivial chance that the surgeon would decline to perform my operation (luckily he was in a confident mood). I went from completely non-functional without glasses to seeing 20/20 in one eye and 20/15 in the other.

While the benefits are diffuse, it's easily one of the top most impactful experiences in my life. It's akin to the feeling of successfully refactoring away a mountain of legacy tech debt that had been getting the job done but bogging you down. Getting rid of the tech debt feels great, but removing the cognitive load of even having to factor it into any decisions anymore just makes things more pleasant.

It's interesting to learn that, indirectly, I owe that to Regan's defense spending.

[noobermin]

Atmospheric turbulence, yes, adaptive optics can ameliorate that. A cloud? No, that won't help with that.

[Someone]

You can’t hit an ICBM early in its flight because you won’t have seen it yet/haven’t figured out yet whether it is heading for you. You don’t want to hit it late in its flight because it will be above your territory, and you don’t want to run the risk of dropping radioactive waste there.

In-between, it is over 100km high up (ICBMs reach heights of >1000km. https://en.wikipedia.org/wiki/Intercontinental_ballistic_mis...)

[gridlockd]

What? If somebody launches a nuclear ICBM, I don't care where it's heading, I want it downed ASAP, preferably right next to where it launched.

An ICBM also likely isn't going to be above my territory when the propellant drops. After that the tiny missile heads are going to be very hard to hit. That's why you need these laser systems in space (the "Star Wars" program) so you can hit them right after launch.

Lastly, the risk of "dropping radioactive waste" is far lower than the risk of having a nuclear warhead detonate at its target destination.

[Someone]

”If somebody launches a nuclear ICBM, I don't care where it's heading, I want it downed ASAP”

Countries do missile tests. Some of them do not announce them because they want to avoid embarrassment when it doesn’t launch or goes boom.

If you attack any launch that looks like an ICBM, you will attack those, too, certainly if you want to down it “right next to where it launched”, as that gives you a very short time to decide whether the missile is armed with nuclear explosives.

I think that what you say comes down to that you’re willing to risk war to deny countries of doing any ICBM missile test.

[gridlockd]

Nobody so far has tested an actual nuclear-armed ICBM. Sure, maybe North Korea is testing ICBMs unannounced, and it's a big problem, but we "know" they aren't nuclear-armed. If the technology existed, these should be shot down, no matter the payload.

> I think that what you say comes down to that you’re willing to risk war to deny countries of doing any ICBM missile test.

"Accidentally" shooting down an unannounced ICBM out of precaution is not necessarily an act of war, nor will it necessarily lead to war.

[derekdahmer]

It’s also against international law to put weapons in space.

[sgt101]

Nuclear weapons, yes. But all weapons - clearly not given all the anti sat tests we've seen.

[CamperBob2]

Who's going to stop them? The international police?

[jandrese]

It would be pretty amazing to see Interpol knocking on the doors of the Raytheon corporate HQ.

[TrainedMonkey]

This bit is specifically about ICBM's, presumably they will be targeted when they are outside of the atmosphere.

[dibujante]

Wouldn't there be more atmospheric interference shooting up than down?

[Depooty]

I imagine it depends on the altitude of the object the laser is targeting. Say if there was a missile flying along the edge of the mesosphere vs a missile 1 km above ground.