SPX500: What if AI leadership is the support?S&P 500 Index CashFX:SPX500armandogoldmanlaszloLast week I framed the market as a sell-the-failed-rally environment. The key question now is why SPX500 has remained relatively resilient while the broader market may be participating less evenly. One possible explanation is concentration: a small group of large AI, semiconductor and hyperscaler names can support a capitalization-weighted index even when breadth, credit and cyclical leadership do not confirm the move. **Main scenario:** if AI leadership weakens while equal-weight breadth, credit and cyclicals fail to recover, the index may lose the narrow support that has kept it resilient and finish the week below its opening level. **Alternative scenario:** AI leadership broadens, equal-weight participation improves, and credit and cyclicals confirm the move. In that case, the short-bias thesis weakens. **Invalidation:** a sustained cross-asset recovery led by improving breadth, credit and cyclical leadership would invalidate the narrow-rally interpretation. **Timeframe:** multi-session observation through the end of the week; daily context. This is a conditional market framework, not an entry signal. **Disclaimer:** This is market analysis for educational purposes only, not financial advice or a recommendation to buy or sell any instrument. Scenarios are conditional and can fail. Manage risk independently.