How did german unrestricted use of submarine warfare impact the allies and united states?

German unrestricted submarine warfare ultimately resulted in the U.S. joining the Allies during WW1 in 1917. The use of submarines was a violation of U.S. neutrality, and it went back on the promise Germany made in the Sussex pledge.

pan-africanism or pan-africanism is a political, philosophical, cultural and social movement that promotes african twinning, the defense of the rights of african people and the unity of africa under a single sovereign state, for all africans, both africa as of the african diasporas.

ba geologist finds four sedimentary rock she determines that no geologic events have shifted the layers she labeles them a,b,c,dbfrom top to bottom