Recently, financial market observers have begun to focus on a potential turning point. JPMorgan warned that the U.S. stock market, after hitting new highs several times this year, may face downward pressure. This warning stems from the Fed's upcoming interest rate cut policy, and the market generally believes this may signal a "fully priced-in good news" situation.

In the face of this prospect, the relationship between traditional financial markets and the emerging cryptocurrency markets has once again become the focus. For a long time, these two markets have shown a close correlation, with fluctuations in the US stock market often triggering corresponding reactions in the cryptocurrency market.

Historically, the relationship between the US stock market and the cryptocurrency market can be likened to "leader and follower". A large number of investors participate in both markets simultaneously, leading to a high correlation in capital flows. If the US stock market experiences a significant decline, it is likely to trigger a panic sentiment among investors, prompting them to sell off high-risk assets, including cryptocurrencies. In this situation, the cryptocurrency market may experience even more severe declines.

However, market behavior is not always constant. In some extreme cases, if the decline in the U.S. stock market is too severe and investors lose confidence in the Fed's ability to stabilize the market, some funds may regard cryptocurrencies like Bitcoin as "digital gold" and attempt to use them as a hedge. However, it is important to note that this shift in market sentiment usually requires a high threshold and is not common.

It is worth mentioning that the cryptocurrency market also has its unique influencing factors. Internal factors such as the Bitcoin halving event, Ethereum network upgrades, and changes in regulatory policies can all have a significant impact on cryptocurrency prices, making their trends not entirely dependent on the performance of the US stock market.

In summary, if the US stock market experiences a sharp decline due to "fully priced-in good news", the cryptocurrency market is likely to be affected by negative sentiment and capital outflows, showing a synchronous downward trend. Although there is a possibility for cryptocurrencies to become a safe-haven asset, the probability is low and resembles a low-probability event. For cryptocurrency investors, closely following market trends and managing risks is crucial.