How Mercenaries Became Ships' Best Defense
Found on Wired on Monday, 22 August 2011

The world's governments are waking up to the sobering fact that the gazillion-dollar warships they've sent to the Gulf of Aden and Indian Ocean can't keep up with the region's elusive pirates. The hijackers' simple, brutal tactics are too effective.
"The final shot worked and the skiff slowed and stopped in the water. They had gotten to within 400 meters of the vessel and realized that an armed team was on board." That realization was enough to end the attack.
One warning shot should be enough. If they don't stop and alter their course, then it's time for fire at will. They attack ships without much of a guilty conscience; so one shouldn't have a guilty conscience when fighting back.