Right out of a WWII B-29

How about the Mk.4 nuke dropped into the ocean outside Vancouver before its B-36 crashed Into the Canadian island? Mk.4 never found.....Oops! Also heard we were 'feet dry' with nukes above North Korea when they pulled some **** during Vietnam, 1968? Can't remember incident. Maybe it was the Pueblo, another Intresting intelligence side story to that....how about nukes loaded into the tubes of a soviet submarine off Cuba and the guys hand on the launch lever? Only a maverick junior soviet officer questioned the pending order as global suicide and cooled the situation.