Already, the line between peaceful merchant ships and naval ones is blurring a little.
Navies are also starting to deploy seamen on merchant ships, something hitherto rare unless the cargo was military.
This was a three-way contest between merchant ships, German submarines and Allied destroyers.
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Thousands of Chinese-flagged merchant ships now cross the ocean each year, giving China plenty of justification for increasing its naval presence.
By 1944 its factories built a plane every five minutes while its shipyards launched 50 merchant ships a day and eight aircraft carriers a month.
At present, warships from a number of countries patrol an international maritime corridor, escorting some merchant ships and responding to distress calls in the area.
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Between 1941 and 1945, merchant ships left Loch Ewe - as well as the Clyde and ports in Iceland - to deliver supplies, weapons and ammunition.
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Between 1941 and 1945, merchant ships left Loch Ewe in Wester Ross as well as the Clyde and ports in Iceland to deliver supplies, weapons and ammunition.
Hawkins paces out just one square foot of foreshore and picks up Victorian plate, modern glass, oyster shell, medieval roof tile, granite ballast from merchant ships and clay pipe stems.
Relief is pouring in from all quarters, and excellent service is being rendered by British and foreign naval and merchant ships in sheltering the fugitives and bringing relief.
Between 1941 and 1945, merchant ships left the loch and also the Clyde and ports in Iceland for the then Soviet Union to deliver supplies, weapons and ammunition.
Unarmed merchant ships were burning within sight of Miami Beach.
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On piracy, it's the policy of some governments, such as Israel, to arm their merchant ships and to teach the merchant marines how to use firearms to defend themselves.
In 2012 the number of successful pirate seizures of merchant ships fell from a 2009 figure of 38 to 21 according to the Combined Maritime Forces (CMF) command in Bahrain but another statistic published by the group highlights a more troubling trend.
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'So far, Member States have, first and foremost, asked merchant and research ships to deploy the 2, 000 drifting robots and buoys needed to maintain the network', explains Mathieu Belbeoch of the JCOMM in situ Observing Platform Support Centre.
Inmarsat began life as a cooperative venture of 64 governments to provide satellite communications for ships (26% of the world's larger merchant vessels now use Inmarsat).
The ship's captain and crew knew they were no match for the German battleship Admiral Scheer but drew its fire to save 38 ships in the convoy and the lives of hundreds of merchant seamen.
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