Cold war would have gone WW3 i think
It nearly came to nuke war with 2 out of 3 SU officers saying fire the nuke or so the story goes (need 3 guys to agree on nuke firing)
en.m.wikipedia.org
"As
flotilla commodore as well as executive officer of the diesel powered submarine
B-59, Arkhipov refused to authorize the captain and the political officer to use
nuclear torpedoes against the
United States Navy, a decision that required the agreement of all three officers. In 2002, Thomas S. Blanton, then director of the U.S.
National Security Archive, credited Arkhipov as "the man who saved the world".