I'm not a pilot (though half the family is) but I do have a lot of experience with big research lasers (PhD in Physics, hence DrKev, big class 4 lasers, have given training courses etc.). It has been 8 years since I've worked in physics but here's what I believe to be the current state of things...
A) The sale of these items needs to be restricted including auction sites, with the capability they have,something similar to firearms laws.
B) Regarding the treatment of the people who choose to aim these at airliners
In the UK and US, sale of any of class 3B or class 4 lasers (anything greater than 5mW power) is illegal to the public. If you do know of anyone selling lasers of Class 3B or Class 4 report them to the appropriate authority (department of trade and industry in the UK). If laws are in place in other countries they will be similar. Online sales might also be covered by this but the greatest issue there is one of enforcement. However, there are no laws relating to the USE of the lasers themselves by anyone. I think that needs be changed in a hurry.
It seems that any arrests made over targeting of aircraft were to do with endangering the aircraft and not to do with use of the lasers as such. A few countries are considering classing lasers as weapons, which would mean that all use without a license is forbidden, but I don't know if anybody has gotten around to that yet.
The potential dangers of even 3B lasers are just too great. Even at the lower limit of class 3B, most lasers are many times brighter than the sun (in terms of the amount of energy per unit area). If you were to look directly into a class 3B laser beam, the blink response of the eye cannot act fast enough to prevent (at least temporary) retinal damage.
What sort of exposure pilots would receive in these incidents is likely to be much lower - exposure does of course depend on the beam diameter (they do spread out a bit over distance), not just a simple dependence on output power. That said, to somebody working in a dark-adapted environment, even a wide-beam (5m or 10m, say) low-power laser will almost certainly ruin dark-adaptation and temporarily impair vision. Much the same as what drivers get with oncoming traffic and full headlamps but possibly worse, certainly more distracting, and of course in a much more critical situation.
"Ladies and Gentlemen, this is your captain speaking. Excuse the short delay, we have to hang around up here for 5 or 10 minutes until we can read the instruments clearly again and our night vision has returned. Hope you're enjoying the flight..."
I once got a "shot" from a 150mW laser, smack bang in the centre of vision. Freak accident - microscope slide falling over into the beam, very freakily passed through the beam at exactly the right angle to hit my eye. It was only the weak reflection that got me. The perfectly circular spot in the centre of my vision took two days to vanish (with no permanent damage, thank God) but it DID scare the ever loving crap out of me. Literally.
It went kind of like this....
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For the record, a class 4 laser is bright enough that even looking at the spot on a wall can damage your vision. Class 4 will also burn skin faster than a lit match, sort of smells like sausages when you do, AND HURTS LIKE
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