To bring a little sanity to this thread, after hearing a pirate interviewed on NPR, they use a speedboat to approach a target, either a tanker or a freighter, they avoid military ships, they are seeking money, not death.
They run up next to the ship at night, use a long bamboo pole with hook on the end to hook a railing, then climb up the pole, armed with a machete or a pistol, make their way to the pilot house, take the watch hostage and demand the captain open the safe.
If the crew is alert, they are ready with firehoses when the pirates try to come over the rail.
If they hava a larger pirate crew they may force the boat into a Somali port, and ransom the crew.
Torpedoes have no place in the story, nor even small arms beyond a machete or a pistol.

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“ The subjects of every state ought to contribute towards the support of the government, as nearly as possible, in proportion to their respective abilities; that is, in proportion to the revenue which they respectively enjoy under the protection of the state.”

Adam Smith , The Wealth of Nations 1776

"We have always known that heedless self-interest was bad morals; we know now that it is bad economics"
FDR's second Inaugural Address