There were several instances of collapse. First, there was an economic crisis due to gas prices in the late 1970s. This crisis combined with Japan's technological exports gave rise to the bubble economy of the 1980s. That was the first instance of urban decay. A lot of places like Detroit lowered in living standards because a lot of the car factories shut down. Meanwhile Toyota and Mitsubishi came in. This is why there was a lot of hate for japanese companies at the time. The second instance was the LA Race Riots in the 1990s. Police men unjustly arrested and hurt a black person, causing a riot to spread in the city. A lot of property damage happened and a lot of businesses failed to recover. Leading to a lot of homelessness and poverty. The third instance is the economic collapse of 2008 caused by real estate speculation and rampant lending to people who could not pay back loans. This caused a collapse at a scale similar to the bubble collapse in Japan. The fourth instance is in 2020, a combination of a large influx of illegal immigrants, COVID, and race riots due to the death of George Floyd. A lot of business closed down and a lot of the public safety of cities went down. Specifically the major urban areas of Chicago, LA, and NY.