The Nation magazine (U.S.) has an interesting short read by Richard Pollak on the market incentives for just letting ocean piracy happen. As it turns out, it is far cheaper for shipping companies to do nothing than to protect their crews:
No reliable statistics measure the annual cost of piracy, but one likely high estimate of $16 billion represents only .001 percent of the more than $14 trillion in world trade that moved by ship last year…
…for years Maersk and most other shipping firms, large and small, have refused to spend the money it would take to make each vessel more secure. Few, for example, have invested in Secure-Ship, an electrified wire fence that delivers a 9,000-volt nonlethal shock to anyone attempting to climb aboard.
Sunjeev Bery 