Alan Greenspan, the former Federal Reserve chairman who shaped global economic policy for nearly two decades, died on June 22 at age 100. His unprecedented 18-year run as the world's most powerful central banker marked a transformative era in monetary policy, influencing markets and governments worldwide through multiple economic cycles.

During his tenure from 1987 to 2006, Greenspan guided the U.S. economy through periods of remarkable growth and stability. He navigated the aftermath of Black Monday in 1987, managed the dot-com boom, and oversaw the longest economic expansion in U.S. history during the 1990s. His policy decisions became templates for central banks around the globe, particularly his approach to interest rates during inflationary periods.

However, Greenspan's legacy carries significant controversy. Many economists argue that the deregulatory stance and low-interest-rate policies of his later years contributed directly to the conditions that sparked the 2008 financial crisis. The housing bubble and subsequent collapse occurred just two years after his retirement, leading to widespread criticism of his market-optimist philosophy.

Greenspan's death marks the end of an era that fundamentally changed how central banks operate. His influence on monetary policy tools and economic theory will continue to be debated by scholars and policymakers for decades, representing both the heights of economic achievement and the risks of unchecked market faith.