It was a fun rid but S&P 500 futures are now back where they were before the FOMC decision. It was a 50-point rise and fall, or about 0.7% in each direction.
If you want to blame anyone, blame Oracle for the decline as Nasdaq futures are underperforming down 1.1% on an 11% share price decline after earnings. The market is getting worried about the AI spending and Oracle just keeps spending more.
If you want a more nuanced answer, this is the usual post-Fed chop. The cut and wait-and-see statement is exactly what was expected so the rally probably wasn't justified.
And a final warning: We're now into the year-end flows part of the year where nothing makes sense and it's all about taxes, position squaring, deleveraging and settling the books, not pure investing or trading.