If the US stock market triggers a circuit breaker, the market may not immediately rebound and could continue to fall (like in March 2020 when it triggered several times), but at least it can help everyone calm down and avoid crazier sell-offs. The number of circuit breakers in US stock market history is low (only 5 times by April 2025), and each time the market has been able to recover, indicating that a circuit breaker is at most an "emergency brake" and does not signify the end of the world.