A new capability may become an option for the Mk 38 Mod. 2 gun mount that is equipping the Webber Class Fast Response Cutters. BAE and Boeing are looking at adding a 10 Kilowatt (13 HP) laser. More here.
“The Mk 38 Mod 2 Tactical Laser System couples a solid-state high-energy laser weapon module with the operational Mk 38 Machine Gun System. The addition of the laser weapon module brings high-precision accuracy against surface and air targets such as small boats and unmanned aerial vehicles. The system also provides the ability to deliver different levels of laser energy, depending on the target and mission objectives.”
I wonder if there is a “stun” setting?
Related: MK 38 mod2, 25 mm, More Than Just a Gun
Chuck Hill's CG Blog 
I wonder if you could mount it to a sharks head…
I’d like to see the parallax adjustment. We just used to shoot the moon.
More here: http://www.baesystems.com/Newsroom/NewsReleases/autoGen_11173015056.html
Reports of a test against a “pirate skiff”: http://www.wired.com/dangerroom/2011/09/lasers-versus-pirates/
“With a laser attached, the idea is to blast multiple skiffs more efficiently: A laser of similar [10] kilowatt expenditure can burn through an outboard motor in about a minute,”
Do you think they will hold still that long? Perhaps the Coast Guard should deploy the “elite” HITRON to take on the pirates if they are going to shoot outboard motors. The HITRON may even get some live fire experience.
Not to mention own ship motion. Not powerful enough to instantly disable an outboard, but probably enough to permanently blind a person if full on the eyes. Not sure where this is going, but turned down it might make a non-lethal persuader.
Against manned aircraft it might blind the pilot. Article seems to indicate a need to kick it up to 100KW to make it militarily useful. That probably would not be that hard, but then it probably would not fit on a Mk38mod2. Looks like they needed a laser for targeting anyway, they just overpowered it and hoped someone would find a use for it.
I am not sure how the general public would take to blinding, even pirates, with a laser. Seems that is perfectly fine to hang a few or have some over qualified SpecOps guys make short range shots but blinding would be an altogether different pile of worms.
If they are to be tired by U. S. law, then something about cruel and unusual would play heavily into any potential trial.
Admiral Porter with the West Indies Squadron wanted to give those pirates a quick and legal trial on board just before he hanged them.
In 1820, the pirate Jean LaFarge attempted to cheat the hangman by jumping over the side in an suicide attempt. He was carefully rescued, brought back aboard, and properly hauled up to the yard (probably the port because the starboard yard was reserved for officers).
Apparently someone is already using lasers or at least very intense light as a means of harassment:
http://www.washingtontimes.com/news/2011/sep/7/inside-the-ring-605847932/
German efforts to weaponize lasers. Some discussion of their limitations. Again a statement that there is an intention to put laser weapons on the Mk38 Mod2 which equips the Fast Response Cutter (and I recently saw a picture of one mounted on an 87 foot WPB).
http://www.defenceweb.co.za/index.php?option=com_content&view=article&id=21429:rheinmetall-successfully-tests-high-energy-laser-weapons-expects-power-to-increase-over-coming-years&catid=50:Land&Itemid=105
A recent update here: http://militarytimes.com/blogs/scoopdeck/2011/11/29/lasers-on-deck/
More evidence that these things are coming, including a photo of a prototype weapon mounted on a Burke class DDG:
http://www.informationdissemination.net/2012/08/time-to-talk-lasers.html
Rheinmetall fields a 50 KW land based demonstrator.
http://www.rheinmetall-defence.com/en/rheinmetall_defence/public_relations/news/latest_news/details_2368.php
The turret they are using appears to be the one normally associated with the Millennium gun, which is a CIWS that is lighter than the Phalanx but depends on a separate firecontrol system.
Israel is making progress in development of laser weapons for use against rockets, drones and some missiles. Good explanation here of their advantages and limitations. https://www.defensenews.com/opinion/commentary/2020/01/17/how-realistic-is-israels-tactical-laser-breakthrough/