Politics, money allocation, taxation, etc. The US had a golden age last century and is now in decline. It can still bounce back but it needs a political and legal revolution, in this particular case, it needs to tax the wealthy and spend it on municipal improvements.
But that's socialism / liberalism and apparently that's terrorism now.
This is a bit of a tangent, but government revenue has skyrocketed in recent decades. Here is an inflation adjusted table. [1] As a percent of GDP it's been fairly stable since the end of WW2 [2], and dramatically higher than prior. But that understates reality because it excludes deficit spending which has increased exponentially since then. So the government is collecting and spending substantially more than back in the golden age, even after accounting for population/economic/etc growth.
[1] - https://usafacts.org/answers/how-much-does-the-us-federal-go...
[2] - https://fred.stlouisfed.org/series/FYFRGDA188S
> it needs to tax the wealthy
The top 1% of earners pay about 38% of all federal individual income taxes, while making up roughly 20% of the nation's total Adjusted Gross Income.
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