In June 2026, Elon Musk became the first trillionaire in history. Never had a single person accumulated such a large fortune. Nor had there been so much talk about taxing billionaires as there is now. French economist Gabriel Zucman (39 years old) has dedicated a good part of his life to investigating how large fortunes avoid paying taxes, ending with a proposal that is "obvious": a fixed tax on the wealth of billionaires. This idea has caused the large fortunes of Silicon Valley to spend almost 400 million dollars to prevent it from becoming a real policy.