Hyperscalers have already outspent most famous US megaprojects
What’s Being Compared and How
- Thread discusses a chart claiming hyperscaler/datacenter capex rivals or exceeds famous US “megaprojects” (railroads, interstate, Apollo, Manhattan Project, ISS, Marshall Plan, F‑35).
- Several argue this mixes unlike things: decades-long public programs vs a short, still-ongoing private buildout; infrastructure vs targeted military/science projects.
- Others say adjusting by GDP or time window changes the story; historical GDP estimates are noisy, so numbers have “wiggle room.”
Railroads, Infrastructure, and Durability
- Railroads and highways are cited as long-lived, broadly enabling infrastructure with century-scale lifetimes and low marginal costs.
- Some push back that not all track survived; many lines went bankrupt or were abandoned, and US rail expansion was driven partly by geopolitics and land subsidies, not just ROI.
AI Datacenters, GPUs, and Depreciation
- Core contrast: rail/roads/fiber last 20–100+ years; GPUs and AI hardware are treated as 3–6 year assets, and performance-per-watt improvements incentivize rapid replacement.
- Disagreement on whether GPUs are “shovels/consumables” or closer to structural steel in a bridge; all agree they are capital-intensive and power-hungry.
Economic Impact, ROI, and Bubble Risk
- Many commenters worry about an AI/compute bubble analogous to 19th‑century railroad manias: massive capex “ahead of demand,” unclear profits, possible painful correction.
- One cited survey claims most firms report positive GenAI ROI, but others note it measures perceived, not measured, returns and may be distorted by internal pressure.
- Concern that private firms need fast payoff unlike public megaprojects, increasing systemic risk if returns disappoint.
AI Capabilities vs Hype
- Enthusiasts see LLMs as already transformative (natural-language interfaces, code generation, translation, knowledge access).
- Skeptics focus on hallucinations, weak disruption of search, questionable productivity gains, maintainability of “vibe-coded” software, and lack of a clear path to “true” AI.
Energy, Security, and Alternative Uses
- Debate over whether datacenter buildout drives new power generation (especially renewables) vs mostly gas/coal.
- Some note GPUs are also critical for simulations, scientific computing, robotics, and potentially warfare; others say classification/security constraints limit reuse of public-cloud GPUs.
Values and Priorities
- Several lament that comparable or larger sums aren’t going to climate, space, or public infrastructure.
- Others see large AI capex as a standard speculative cycle; market will eventually reprice if expectations are wrong.