Cryptography began as a wartime necessity: a means of concealing information, protecting strategy, and gaining advantage in moments of extraordinary consequence. In the decades since Turing’s time, it has moved from military intelligence into the center of modern life, shaping how we communicate, bank, vote, and establish trust in a digital world. As computing power grows and security challenges multiply, cryptography raises questions that are no longer merely technical: Who gets privacy? How is trust built between strangers? And what does it mean to keep something secure when so much of modern life depends on systems most of us never see?