Excuses, excuses, excuses.
After it all hit the fan, poor Zimmermann was called before the German parliament to testify about his little telegram. He admitted to sending it, but acted like he couldn't quite understand what the problem was. His speech is filled with gems like him trying to explain how, because he didn't send the telegram to the president of Mexico directly, it meant that it was really nobody's business and could everyone just leave him alone. Kthanksbbye.
Next time you get caught texting in class, try asking your teacher, "Why do you care? It's not like I was texting you." See how that goes.
Also, have fun in detention.
The Fourteen Points is probably the most important document/speech to come out of the First World War. President Wilson really did think that he had a plan that would make it so that nations no longer went to war with each other. As if war was a disease and he had the cure.
Most of the points are about trying to get the nations of Europe to stop fighting with each other so darn much, but points number one and two directly relate to the Zimmermann Telegram.
In point one, Wilson demands "Open covenants of peace, openly arrived at, after which there shall be no private international understandings of any kind but diplomacy shall proceed always frankly and in the public view." Take that, all you coded message-senders trying to make alliances in secret.
Point two makes it clear that there is to be "Absolute freedom of navigation on the seas," which of course translates to "Germany needs to knock it off with all that unrestricted submarine warfare stuff if we're ever going to have some peace and quiet around here." And we all know that unrestricted submarine warfare was the raison d'être of the Zimmermann Telegram.
Wilson may come across as an arrogant, bossy old coot in his Fourteen Points. But hey, God did the same thing in just ten points, right? Some of the Fourteen Points were implemented after the war and others were ignored. To Wilson's credit, the points of his that the world dismissed were some of the causes of World War II.
The British Prime Minister was very happy when the U.S. finally joined World War I. Like so happy it was as if the American Revolution and the War of 1812 never happened. He doesn't quite apologize for all the unfair taxes and burning down the White House, but he comes close. Mostly he talks about how the Germans are the worst and should just go home already, and how the French are kinda useless, but it's not their fault; and then he repeats how just so gosh darn happy he is to have the Americans on the same side as the British for once.
The Emperor of Germany had a tradition of going out on his balcony and basically raving about whatever was on his mind for anyone listening. Some of those talks were a little crazy-town. Wilhelm wasn't always one to choose his words carefully; he just spoke his mind. Or apparently yelled it at the crowds below or sometimes at the assembled German armed forces.
If you think that announcing unrestricted submarine warfare in the Zimmermann Telegram was a blunt and ill-reasoned military strategy, just wait until you've heard some of what the Kaiser had to say. He was like an overexcited child with an actual military instead of toy soldiers. He recklessly picked a fight with most of Europe that resulted in a humiliating defeat for Germany and led to another disastrous global conflict twenty years later. The German naval brass convinced the Kaiser that unrestricted submarine warfare was a great idea that would have Britain begging for mercy in a matter of months.
You can see why he would have approved of the meddling scheme proposed in the telegram.
Zimmermann did some things right, from Germany's perspective.
The German Foreign Office had been secretly encouraging radicals in Russia throughout the war, sneaking them back into Russia when they were exiled, giving them money to print communist propaganda, those sorts of things. It all paid off when Tsar Nicholas resigned and Russia plunged into chaos—the kind of chaos that would make them unable to continue fighting Germany.