Deutschland: The World’s First Merchant Submarine
The British naval blockade of the Central Powers created shortages in food and strategic materials such as rubber, nickel and tin.
Britain and France protested against the use of submarines as merchant ships, arguing that they could not be stopped and inspected for munitions like other cargo vessels. The U.S., under pressure for showing favoritism while having declared itself neutral, rejected the argument. Unarmed submarines were considered merchant vessels and allowed to trade.
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