Since March, four U.S. banks have failed or been acquired, showing small and medium-sized banks' vulnerability and macro risk. These banks have unique business models and vulnerabilities, such as Silicon Valley Bank, First Republic Bank’s robust customer structure, poor deposit stability, and Signature Bank and Silvergate Bank’s involvement in high-risk encryption industries. Changes in the macro environment, deregulation, inherent vulnerability, and weak risk control capabilities of commercial banks have jointly led to the crisis. The pressures faced by small and medium-sized banks include outflow pressure on the liability side, high-interest rates, and credit risks. Although the probability of a systemic crisis is low, the hidden dangers of high industry concentration and "too big to fail" have increased.