The basic rule with diode lasers is this. The more powerful the beam, the quicker it expands in diameter. The beam is focused such that at a very small distance from the aperture, you might be able to light a cigarette...or melt a hole in a black plastic bag. Prior to, and beyond this small area...the beam will NOT light a cigarette nor melt black plastic.
We must not succumb to the image of the "Star Trek" type phaser beam....they all disperse with the square of the distance away. As the knowledgeable poster on Page one said....the best lasers shot at the moon are 5 times the moon's diameter when they arrive there. If you were to look at the Earth from the moon (directly into the beam) you would most certainly NOT notice it.....it is that diverged.
For aircraft.....the beam operate the same way. It is very much wider (and hence weaker) than the millimeter beam width at the aperature. Combine this with topside cockpit windows, layed down at 45 degrees or more to the vertical, makes the beam pale in comparison to the landing lights on your wingtips.
IMO, people should not aim their lasers at planes and helicopters....in the rare instance where the impinging beam might refract in such a way as to briefly distract the pilot flying. And as such I do not think the "hang 'em high" attitude needs to be taken in light of the well known facts and physics of collimated(sp) monochrome light.