What wad unrestricted submarine warfare

Unrestricted submarine warfare is a type of naval warfare in which submarines sink vessels such as freighters and tankers without warning, as opposed to attacks per prize rules (also known as "cruiser rules").

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explanation:

the big stick policy was to still look powerful, and be nice at the same time. the big stick policy was also to countries who were at war, find peace with eachother.

the dollar diplomacy was to expand american business and get it to latin america, for that would be good for the economy.

you my friend, your regards.

agubaba khaleekha.