Final answer:
The lesson not learned from Hurricane Katrina was widespread public approval of the government's response. Instead, it was marked by significant public criticism over the lack of clear leadership, poor government preparedness, and inadequate communication between agencies during the disaster.
Step-by-step explanation:
The lesson not learned from Hurricane Katrina, according to the Congressional investigation, was B. Widespread public approval of the government's response.
Following the disaster, there was a general consensus that the federal government and specifically the Federal Emergency Management Agency (FEMA) were not adequately prepared for a disaster of this scale. The direct aftermath highlighted several critical issues such as the lack of clear leadership, the government's lack of preparedness, and poor communication between responding agencies. However, widespread public approval of the government's response was not observed; in fact, there was significant public criticism and disappointment with how the disaster was handled. This sentiment was particularly evident with respect to the federal government's slow response in deploying aid and the impact of socioeconomic and racial disparities, which intensified the perception of an inadequate response.
The disaster revealed that the nation's emergency response system was flawed, especially concerning coordination and leadership roles between federal, state, and local governments. The crisis was exacerbated by an unclear division of responsibilities and authority during the response phase, resulting in delayed action and inadequate logistical support. This was a stark contrast to the successful rescue operations by the U.S. Coast Guard, which managed to save over thirty-five thousand people. Despite this, Hurricane Katrina remains a prime example of the failure of federal emergency response and preparedness, ultimately leading to reforms and changes in the structure and management of FEMA and the broader emergency management framework.