Before there were phones and technology, people had to communicate with each other in a good old-fashioned way, by writing letters. While writing letters as a medium still exists and is still occasionally used, it does not have its old popularity. History has seen its fair share of important letters that have made changes.
One letter that I have never heard much of but seems an important element in some sort of aspect of development is the Eistein-Szilard letter. Szilard wrote a letter to President at the time Roosevelt, explaining how he and another scientist were working on the development in nuclear science. Einstein signed off on this letter, potentially believing it important for the President to be aware of modern (for its era) capabilities of science in warfare, believing the knowledge to be dangerous in the wrong hands. Roosevelt promised funding for Szilard’s research and when that money was slow to come, Szilard threatened to release sections of his work that could potentially reveal how he was creating the very things that he was working on. Einstein later regretted signing off on the letter because of the subsequent creation of the atomic bomb that came about because of the development that this letter prompted.
I will never stop believing that words have power. The things we say or even write an have an effect. It is not insignificant, the things that have happened in history in response to writings and perhaps, in the future, there will be more to come.