You need a government willing to invest and spend trillions on their policy agendas (clean energy, etc). You need a government that recognizes the enormous power that capital and finance have, and moves to curtail them.
FDR did this, and Wall Street hated him. Post WW2, during Bretton Woods, the conference that would decide the economic fate of the world for 2-3 decades, no banker was allowed to attend.
People have forgotten but Bretton Woods was a planned economy. Fixed exchange rates, fatories told what not to and what to produce. The government intervening to keep the costs of goods to a certain level.
The post war boom was a highly controlled experiment by New Dealers that had lived through the Great Depression and wanted to avoid such a scenario at all costs.