The basis of thee Great Depression was the collapse of the World’s reserve currency, the British pound - not stock valuations, and not Smoot-Hawley tariffs.
Market has built in the Trump tax cuts, deregulation, trade agreements, repatriation of offshore funds, manufacturing expansion, oil production dominance. And all that is just getting started in a historical context.
This dip is centered on tech spilling over to the composites. Tech is due for a hit because of their chicanery which is just now being exposed. There will be massive lawsuits coming that will last for years.
Eh, that’s the special sauce Shiller P/E — which looks to the last 10 years. That means with all the earnings suppressed by the crash of 2008 and eight years of Obama.