The Philippine Navy has been arming small patrol boats with portable anti-tank missiles, such the Israel's Spike. This is a fire and forget missile, which has a range of about 8 kilometers. It’s easy to operate, even when the launcher is bolted to the deck of a small speedboat. The seagoing Spike has proven useful in dealing with pirates, since the missile reportedly can blow out a hole in the hull of a fleeing, fast moving, pirate ship.SP goes on to explain that such weapons in the wrong hands could cause trouble for non-pirates, such as a merchant ship or Naval vessels.
Time to bring back heavy side armor for warships?
The USS New Jersey (BB-62) had armor up to 12 inches thick in places...(info on battleship armor here and here)