Air gaps are harder than they sound.

Air traffic control now uses ADS-B data linked from aircraft. Anyone with a plane and a few thousand dollars for an ADSB-out unit (required on all aircraft in a few years) is sending data to the air traffic control computers. Is the data sufficiently checked for hacks from badly-formed packets etc? I'm sure its checked but people have managed to hack other systems that were thought to be secure.

Air traffic control may also need feeds from NOAA weather, which will need to get data from and provide data to many outside services.

Utilities may have internet connectivity to allow employees to quickly fix problems from home.

Even with air gaps, systems often need new firmware or software, so you need to control all of the computers where that development is done, or need a way to be sure the software doesn't have hidden time bombs.

I'm not saying that its impossible, but it can be quite difficult to completely secure a system from sophisticated hacks.

We don't have widely accepted rules of war for cyber-warfare. It has the potential to escalate into acts that cause civilian deaths, and large scale property damage. Does a cyber attack on nuclear strategic forces result in a nuclear counter-attack - the way a conventional attack might?

IF the US is behind this, the initial response may seem reasonable, but it could lead to escalating counter attacks and real badness.

This is very spooky uncharted territory.

I think the police should have exactly as much or little right to create a fake account on a site as any other person does.

Impersonating someone real should be illegal if it isn't already .

Sony makes a, by all reports, terrible movie. Suddenly the hack gives it a tremendous amount of press coverage and controversy. When they finally relent and release it, will the overall ticket sales be up or down?

Nah, Sony is much too honest and honorable of a company to consider such a thing......

The only demo I saw of one of these was against a small boat.

Missiles might be a valid target, but they could be designed to be very laser resistant - picture a reentry shield......

I don't really see much use for these anyway - "won't work in rain and fog" is a pretty big problem.

A modestly shiny piece of metal will do quite a good job of reflecting. You won't get a coherent beam but a diffuse spot that will still blind at a long distance. think of the sun reflecting off of a modestly well polished metal surface. Something you could easily get with a buffing wheel.

Or for more humor value - a disco ball......

I'm worried about a reflector on the target ship. If I were planning a terrorist attack on a US navy ship, after reading this, I'd mount an optical retro-reflectors. (though of course that makes you more radar-visible... The retroreflectors are a big hazard to crew on the firing ship. They don't need to be very good if you are just trying to blind, not do physical damage.

The blinding problem is more an issue if the ship is in harbor somewhere. There is also the risk of a clever terrorist on a boat reflecting the beam toward a nearby (few kilometers) set of civilians - say a crowded beach.......

Reasonable precautions can avoid these scenarios, but the precautions need to be taken very seriously. I don't want to hear that we accidentally blinded hundreds of innocent families on a beach somewhere.....

(I just hope that the US realizes the risk before the terrorists recognize the opportunity). Otherwise I wouldn't even post ideas like this on a public board.

This could get sticky. The most effective property of the lasers may be that they blind, even though that isn't their stated function. Similarly to using white phosphorus against humans, the legality is debated.

Everyone on a ship with the laser will need eye protection all the time. Crude metal corner cubes will be pretty effective and since the goal of the weapon is rapid response, the crew will need to always be ready, or they risk blinding their own people. It will have a really tough time burning through a 1/4" thick aluminum corner cube.

Note - it isn't clear from the article whether the laser operates at a wavelength that is likely to cause blindness. Various hints suggest it is Nd (or maybe Yb) based which would be ~1um and is in a wavelength range that can easily cause blindness (it is focused by the eye). The powers required for blinding are dramatically lower then the power required to do physical damage, so its range as a blinding weapon (intentional or not) will be much longer than its range for physical damage. The risk of blinding bystanders from scatter may be significant.

If it is ~1um micron wavelength the beam will be invisible and targets may not be aware of how they were damaged or blinded.

Are you so sure?
How many lives were lost in WWII to protect freedom? Would we allow an authoritarian government that didn't support human rights to take over the US because fighting would mean we would lose millions of lives?

Generally fighting fire with water or other fire retardants is the preferred method.

It is in the very nature of evil that it "gets results". The entire point of morality is that there are things you will not do even if they are in your interest.

As an American citizen, I do not in any way approve of the use of torture. I am willing to accept the higher risk of death by terrorism, assuming the risk even is higher, in return for the country behaving in a moral fashion. I am willing to trade my safety for doing what is right. No torture, no indefinite detention, no extra-judicial killings.

  If I knew a legal way to stop the US from using torture, I would.

We have become the things we always claimed that we opposed in the world.

Superconducting linacs can be quite efficient - 10s of %. Electric costs are not a major driver for most accelerators so typically they are not that good in order to save construction costs. You could probably design >50% wall plug -> beam efficiency accelerator if you wanted to.

Laser accelerators are not that good at converting laser energy to beam energy. I don't know the numbers, but above ~10% would surprise me. Then the high drive lasers are very inefficient (these are not diode laesrs!). Both those can be improved, but I would be surprised if the final efficiency were as high as for a conventional superconducting linac.

For low power beam applications that may not be a significant disadvantage and the short length is of course a big advantage. (though the drive laser is big).

If older computers can do the job and are known to be reliable in this environment, then using them is the correct choice. We sent people to the moon, and Voyager to multiple outer planets with much older computer technology.

If newer computers would provide improved performance IN THIS APPLICATION then they are worth considering.

We need to test all the competing technologies for this to pick the best:

1) high power lasers.
2). Flame throwers
3). High power plasma discharges.
4). rocket-propelled Anti-leaf attack drones
5). Jets of ClF3
6) Anti-proton beams.
7). Brushes
8) US only: a guy walking ahead of the train with a broom.

then we can see which is the most cost effective and safe - and get some cool youtube videos as well.

I wonder if Sony knows that they are still losing business over this - probably no way for them to find out. I know they've lost >$10K in sales from me since then (I had all Sony stuff at home until then, now nothing).

I feel sorry for their employees who's information was compromised, but I can't say the same about the company. They are still on my "do not buy" list, and I buy a lot of the sort of things that they sell. Still waiting for an apology for the rootkit.