On the naval side I'd imagine just pumping a ton of sea water mist into the air should work. And if a laser hits it then...it just turns to steam...which also blocks the laser.
Simply don't move into direct line of sight of an American ship and fire over-the-horizon weapons at it? Or torpedos. Or supersonic aircraft firing supersonic anti-ship weapons (e.g. the Indian BrahMos).
Lasers, unlike SAMs, have a very limited spear of effect.
That's not much help if you're in a ship, where a) you'll be close to sea level and b) incoming missiles etc. will be flying low to avoid radar, rather than high up in the air where they can be convenient targets.
Lasers can fire all the way to the moon, and it might be a great idea to put military ones on top of mountains one day, depending on the weather, but if we're talking about lasers on ships...the USS Nimitz (the largest aircraft carrier class) has a height of about 36m above the waterline, so the distance to the horizon is something like 20km or ~13 miles.
The Retroreflector (link: http://en.wikipedia.org/wiki/Retroreflector) would reflect the laser back. However, I guess that laser with 30 kilowatt power would melt a cheap mirror.
High powered lasers 15 to 30 years from now won't be powerful enough to burn through gas and smoke nearly instantly? Wouldn't the laser just destroy the smoke particulate?
