[tripletao]

I spent some time looking for sources for the various "railroad investment as % of GDP" numbers floating around, and I don't think they're very good. The modern concept of GDP didn't even exist back then, so the denominator is calculated in retrospect from the limited contemporary data. The numerator is more confident, but the papers I found mostly showed closer to 3%. A pretty wide range is at least defensible though, and I guess VCs are comparing against the high end for obvious reasons.

https://news.ycombinator.com/item?id=44805979

This AI investment is interesting because it's mostly not in durable goods, unlike the railroad's rails and (most importantly) land. The buildings and power infrastructure for the datacenters could retain value for decades, but the servers won't unless something goes badly wrong. I believe this is the largest investment in human history justified primarily by the anticipated value of intellectual property.