This is a far cry from the first subsea cables laid in the 1850s between England and France, with Europe and the US linked via telegraph in the 1860s. While brief messages took hours to decode, the cables opened a new age of intercontinental communication. Today, tools like ChatGPT rely on an ocean-spanning web of ultra-fast connectivity, fueling a wave of investment in new cables. The stakes are massive: spending on cable systems is projected to surge to $15.4 billion by 2028, from $900 million...