[The US stock market once again set a new high, but they insist on being short: the US stock market will collapse at any time!] On Wednesday, the S&P 500 index hit a new record high, rising 0.86% to 5248.49 points. As the US stock market has continued to rise in the past five months, "breaking new historical highs" seems to have become a common occurrence for US stock investors. But on Wall Street, there is also increasing discussion about when the current US stock market rally will end. If you ask Dubrovko Lakos Bujas, Chief Global Analyst at JPMorgan Chase, his answer could be: "The US stock market could collapse at any time, and investors would be caught off guard."