The agency attributed the increase in disposable income to the nation’s economic growth, with GDP expanding 2.35 percent last year from the previous year despite the impact of the pandemic. In other words, the wealth gap has not improved despite increases in people’s average disposable income and GDP. Former US president Barack Obama once said income inequality is the “defining challenge of our times,” while Pope Francis tweeted that “Inequality is the root of social evil.” Many experts believe income inequality inevitably leads to social instability and disorder, and even political turmoil. Wu’s analysis also found that perceived unfairness in wealth distribution reduces non-rich citizens’ willingness to fight for their country by dampening their national pride, a key element in psychological attachment to national identity. Wu’s research highlights the importance of an equitable distribution of wealth and resources, and, more importantly, it suggests that unfairness in wealth distribution threatens national security.