A worldwide stock sell-off is underway led by SpaceX, bad news for tech investors and anyone heavily exposed to the AI boom.

• SpaceX lost $400 billion in one day, one of the biggest single-day wipeouts ever, leaving IPO buyers underwater.
• The drop is global: South Korea's market fell 10% and had to be halted, with chip giants Samsung and SK Hynix down sharply, and US tech futures sliding.
• SpaceX plans to keep burning cash until 2030 and borrow heavily, raising doubts about its high credit rating and whether moon, Mars, and space data center promises will ever pay off.
• Foreign and Chinese money is pulling out of Asian markets, and funds like Apollo are limiting withdrawals as investors rush to get cash out.
• Even SoftBank's Masayoshi Son publicly called space data centers pointless, saying the AI race will be won by computing on Earth.

Outlook: Expect more downside and louder bubble warnings as leverage unwinds and Musk risks losing trillionaire status.