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<div dir="auto">Jul 16, 2026 at 3:37 AM by cryptography@metzdowd.com:<br></div><blockquote class="tutanota_quote" style="border-left: 1px solid #93A3B8; padding-left: 10px; margin-left: 5px;"><p data-start="954" data-end="960">Hello,<span></span><br></p><p data-start="965" data-end="1040">I have been studying the Bitcoin protocol and would like to ask a question.<br></p><p data-start="1045" data-end="1194">In your opinion, what is currently the biggest long-term security challenge for Bitcoin: quantum computing, mining centralization, or something else?<br></p><p data-start="1199" data-end="1232">I would appreciate your thoughts.<br></p><p data-start="1237" data-end="1247">Thank you.<br></p><p data-start="1237" data-end="1247" style="font-family: Arial, sans-serif; font-size: 14px; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);">James Lancaster<br></p></blockquote><div dir="auto"><br></div><div dir="auto">Hello James,<br></div><div dir="auto"><br></div><div dir="auto">Thank you for the interesting question.<br></div><div dir="auto"><br></div><div dir="auto">Before discussing Bitcoin’s security and its problems, I want to emphasize my deepest respect for all its developers and their work.<br></div><div dir="auto"><br></div><div dir="auto">The long-term risk is that the network’s security is financed out of the price of an asset whose free float is small and whose ownership is concentrated, while the opportunity cost of mining capacity is now set by the AI market.<br></div><div dir="auto"><br></div><div dir="auto">For the first time, mining infrastructure has a permanent, better-paying alternative buyer for the same megawatts. Bitcoin’s security budget now has to compete with the AI market for the same energy, while the subsidy halves every four years. The old question was whether fees would be enough after the subsidy fades. The new question is whether fees can outbid the AI rate for the same power.<br></div><div dir="auto"><br></div><div dir="auto">This is the long-term challenge.<br></div><div dir="auto"><br></div><div dir="auto">—<br></div><div dir="auto">Alejandro<br></div><div dir="auto"><br></div><div dir="auto">«You can’t parallelize your way out of time.»<br></div><div dir="auto"><br></div><div dir="auto"><br></div> </body>
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