US Stocks Diverge as AI Spending Returns Eyed; Microsoft, Alphabet, Amazon Earnings and Fed Meeting Ahead

The rotation into small caps while megacap tech slipped suggests the market is beginning to price AI capex as a cost question rather than a pure growth story — a meaningful shift for the companies carrying the heaviest spending burdens. This week concentrates that test: the three hyperscaler earnings land alongside a Fed decision and key inflation and growth data, so any read-through on AI returns will be filtered through macro noise. Whether the small-cap bid persists if megacap results disappoint is the open question worth watching.