Comment by solatic

You are correct, but only insofar as destroying paper value. If investors have a firesale because the market would prefer to realize whatever value might be rescued, even at a loss, but the proceeds of the sale stay inside the US, then that capital is more likely to be reinvested in the US once investor confidence returns. This is the underlying reason why most long-investors should continue to hold their positions despite short-term losses. The fact that NVDA has a $4.6T market cap, as a product of about 24 billion shares multiplied by about a $190/share price, does not mean that the market believes that all 24 billion shares could be sold for that $190/share price. That is a convenient fiction that falls apart when investor confidence bursts, but that does not in and of itself truly represent value destruction (Nvidia employees will still wake up the next day and go to work), at least not until second-order-effects kick in (e.g. Nvidia employees leave because their RSU packages are no longer competitive compensation). People who stay long in the stock market can wait for investor confidence to return, in which cash is reinjected into the stock market, and the losses in diversified portfolios are not realized. If the S&P 500 investor takes a 50% hit in a crash, decides to hold, then the S&P 500 rises by 140% in the next two years, then the investor who held will still realize a nice return.

The way in which that narrative does not happen is if the capital leaves entirely to be locked up in other investments; in the context of index funds which would anyway rebalance to rise with those other investments, if the capital leaves for other countries, to investments that are not covered by the index funds.