Doomberg:

In his weekly newsletter Tree Rings, Luke Gromen has been arguing persuasively that the US stock market now effectively backstops the US Treasury market. With foreign buyers limiting their purchases of US debt, any meaningful fall in stock prices would trigger a significant crisis for the Federal Reserve. The primary drivers of this direct linkage are the persistent US fiscal deficits and the strong correlation between government tax receipts and equity prices. Should a major market correction occur, deficits would surely blow out beyond what can reasonably be managed absent direct monetization.
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It is no exaggeration to say that these three pillars—NVIDIA’s designs, TSMC’s foundry expertise, and ASML’s near monopoly on the most advanced lithography machines—form the foundation of the current stock market boom.