How did submarine warfare impact the U.S. decision to enter the war? The United States felt they could positively impact the war for Allied forces through new submarine technologies. The United States felt compelled to enter the war in response to Germany's use of submarines to kill civilians. The United States entered the war because Germany used submarines to destroy British shipping. The United States entered the war after Germany destroyed American-made submarines.

The uses of submarine warfare by the Germans forces impacted US to enter the warfare as it led to massive killing of its civilians.

What impact submarine warfare had in war ?

In WWI, Britain blocked the North Sea and English Channel to cut the food, war supplies and fuel supplies to Germany. Germany strike back by destroying the supplying neutral ships of the allies by using submarines with the motive to starve the allies.

On May 7, 1915, German submarine the Lusitania, killed 1200,people including 128 Americans. The United States President Wilson ordered to enter the war in response to Germany's use of submarines to kill civilians.

Therefore, option B The United States felt compelled to enter the war in response to Germany's use of submarines to kill civilians.

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