The last financial crisis was in 2007, when the U.S. subprime mortgage crisis triggered a global financial tsunami. The main reasons for the subprime mortgage crisis are the following three points: (1) Poor quality of underlying assets

The real cause of the U.S. subprime mortgage crisis is not the asset securitization tool itself, but the subprime underlying assets of asset securitization. Caused by poor loan quality and excessive use of asset securitization. The problem lies in the subprime loans underlying asset securitization products. The lax risk prevention and control in the issuance of subprime loans has led to poor quality of subprime loans. At the beginning of the 21st century, the United States suffered a severe economic recession due to the double blow of the bursting of the technology stock bubble and terrorist attacks. The U.S. government took various measures to stimulate the economy, the most important of which was to increase the homeownership rate of American families. The Federal Reserve cut interest rates 13 times from 2001 to 2003, with the nominal interest rate falling from 6.5% to 1%. It also launched the "American Dream Down Payment Act" to require lower down payment ratios for low- and middle-income families, and required Fannie Mae and Freddie Mac to Government financial institutions must include a certain amount of housing loans for poor people in the bank mortgages they purchase.

Home loans have also introduced zero down payment, non-certificate loans, etc., allowing many families and individuals who are completely unable to repay the loan to buy a house. These risky mortgages with low repayment capabilities are called "subprime loans." The scale of these subprime loans expanded rapidly under the macro environment at that time. By 2007, the scale of subprime loans had accounted for half of the securitization market. (2) Excessive use of asset securitization

Asset securitization was born in the United States in the 20th century. This financial innovation broke the separation of the American financial market and connected the direct financing market and the indirect financing market. stand up. Simply put, asset securitization means that investment bankers package bank loans into bonds. After the bonds are sold, the bank can continue to issue loans. Therefore, asset securitization solves the bank's liquidity problem and improves the bank's lending ability. magnified several times. Bank loans belong to the commercial banking system, which is the indirect financing market, and bonds belong to the investment banking system, which is the direct financing market. Before asset securitization, these two market systems were operated separately, and asset securitization opened up the boundaries between the two markets. , established a unified financial market system, thus also promoting the rapid development of the financial industry.

After decades of development, asset securitization in the United States has extended to various types of assets, such as home mortgages, car loans, student loans, accounts receivable, etc. Asset securitization products are available all over the United States In the capital market, asset securitization products are securitized again. The leverage ratio is also increased during the securitization process. Therefore, asset securitization greatly extends the chain of assets and amplifies the risks of assets.

The root cause of the U.S. subprime mortgage crisis is subprime mortgage loans. By 2007, the scale of U.S. subprime loans reached 780 billion U.S. dollars. These subprime loans have been securitized many times to create There were 73 trillion US dollars in financial transactions, several times the underlying assets, and huge-scale financial transactions penetrated into many areas of the U.S. economic system. Therefore, when house prices fell, subprime mortgage loans defaulted. As the default rate increased, a subprime mortgage crisis emerged with subprime loans as the underlying assets. Later, it spread along the chain of multiple asset securitizations to The subprime mortgage crisis broke out in the entire U.S. financial industry, as well as the U.S. economic system and even the world economic system. (3) It is difficult for the financial regulatory system to control subprime risks

For example, there are 52 states in the United States, but the Federal Reserve has only divided it into 12 reserve areas, and each reserve area covers several states. Each reserve area has a high degree of independence, and the interests of the local governments under its jurisdiction are partially converged. The financial regulators of each reserve area speak for the interests of the area under their jurisdiction. In addition, in addition to the Federal Reserve, the United States also has many financial regulatory agencies such as the Office of Oversight of Thrift Institutions, the Securities and Exchange Commission, and the Commodity Futures Trading Commission. Some of these agencies are industry associations, and some are affiliated with other departments of Congress. Each has different regulatory strengths. , the cost of supervision also varies. Financial companies in the United States often seek a more relaxed operating environment and lower regulatory fees by changing their registration agencies, and various regulatory agencies will also implement various preferential measures to attract more companies to include them. regulatory system in order to gain greater influence and more regulatory revenue. The entire regulatory system is severely fragmented.