Why didn Zimmermann deny his telegram?
Here is what Barbara W. Tuchman had to say in her book “The Zimmermann Telegram”, (Dell Publishing Company 1965) at 168-9 (paperback edition): What led Zimmermann, who…was both astute and resourceful, to commit this historic boner, is not known. That he was too stunned to think clearly is unlikely, for the Germans had had two days to consider their answer and Germans do not issue official statements off the cuff. Most likely it was simple German arrogance that decided him to brazen it out in the belief that American hostility was of no account and could not change the situation before the submarine war was won anyway. At Zimmermann’s press conference, just before the fatal words were spoken, William Bayard Hale, who was in Berlin as Hearst correspondent, tried to head him off. Hale, the ex-clergyman and ex-friend and agent of Wilson, was at the time and had been for two years a paid German agent, under actual contract to the German government at $15,000 a year as propaganda adviser t