Unrestricted submarine warfare is a type of naval warfare in which submarines sink boasts, such as freighters and tankers, without warning. germany started following this policy in 1915. how does this affect tensions with other countries such as the united
states?

The German submarines or the "U Boats" attacked many vessels that were transporting various goods and supplies to the German enemies such as France, Britain, Belgium, etc.

However, this strategy proved to be devastating on the long term as Neutral nations like USA turned agains the Germans because of Germany destroyed ships and vessels of their countries. It was not just ships, the crews of these ships were killed as well. This is one of the primary reasons that usa declared war on Germany during the 1st world war.

Explanation:

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