Is Bitcoin's security budget actually a problem, or is it FUD?
The measurement is not controversial. Bitcoin pays 0.82% of its market capitalisation a year for security, and 0.41% after the 2028 halving, price-independently. What is genuinely argued is whether that is too little — and that argument has not been settled by anyone.
What is measured, and not in dispute
Miner revenue and market capitalisation are both public. Their ratio today is 0.82%. Halving the subsidy on schedule and holding the fee component flat gives 0.41% after ~April 2028. Nobody contests these; they are arithmetic on published series, and you can reproduce them from mempool.space and any market-cap source in a few minutes.
The case that it is not a problem
Four arguments, stated at their strongest. Fees can grow. Block space is scarce and demand for it is young; a mature fee market could be far larger than today’s 0.64%. Price can rise. A higher bitcoin price raises the dollars paid to miners even at a constant ratio, and dollars are what buys hardware and electricity. Attacks are not free at any budget. An attacker must acquire hashrate and accept that a successful attack destroys the value of what they attacked. No floor has been derived. The 1% figure is a heuristic, not a result; Hasu measured the ratio at 2% in 2020 and declined to name a floor precisely because he could not derive one.
The case that it is
Three arguments. The ratio is scheduled to fall and the schedule is not negotiable. 0.82% becomes 0.41% in 2028 and 0.21% in ~2032 whatever price does, because price cancels. The fee growth required is far outside the record. Fees would need about 18% of miner revenue permanently, 29× today’s level; the longest Bitcoin has held above 20% is 40 days and it has never held above 30% for a single sustained stretch. The window closes quietly. Nothing breaks on the day of a halving; the budget simply becomes smaller, and the cost of an attack falls with it.
Where that leaves it
Both sides accept the same table. The disagreement is over the floor, and the floor is a judgement nobody has grounded in an attack model. What survives the disagreement: at 0.5%, the bottom of Alden’s published band, there is no gap today — and there is one from 2028 at any floor in the published range. That is the narrow claim these pages make. Anything stronger is opinion wearing arithmetic’s clothes.
| Basis | Ratio | Gap / yr | Market cap to cover it |
|---|---|---|---|
| Trailing-year revenue over spot market cap | 0.92% | $1.27B | $24.40B |
| Trailing-year revenue over average market cap | 0.86% | $2.13B | $40.93B |
| Spot run-rate revenue over spot market cap (published) | 0.82% | $2.77B | $53.28B |
Three ways to measure the same ratio, all published. None of the three closes the gap.