Why Was the Attack on Pearl Harbor Significant

Why was the attack on Pearl Harbor significant?

A) It demonstrated the Japanese naval commander's belief that the only way Japan could defeat the United States was through a long war.
B) It showed that the United States was too quick to lift embargoes on Japan and other warring nations.
C) It was a surprise attack that immediately caused the United States to enter the war and brought the isolationist movement to an abrupt end.
D) It was a highly successful victory for the Japanese militarily due to their destruction of U.S.aircraft carriers.
E) It caused the war henceforth to become more localized in the Pacific and less of a global conflict.