Letter: How secure are 21st Century nuclear weapons from cyber attack?

To The Editor, The world is facing three existential threats: climate change, nuclear weapons, and AI. I would like to point out that all three are interconnected. Perhaps what is most worrisome is the real threat of 21st-century nuclear weapons being hacked. I would like to raise the alarm about the two trillion dollar “enhancement” or “modernization” of  US nuclear weapons.