The volatility of earnings per share over time

Take the SP500, price and earnings adjusted for inflation, and plot that over time. Macrotrends has it. Looking at this chart, I see EPS begins to become volatile since global trade accelerated. So EPS has become a global variable and half the income of the American multi-nationals is from foreign traded.The mean value of that EPS is rising with trend, but its swing has become twice the mean, only recently. That tells me the price will swing.

The catch is that American employment if closely coupled with the fortunes of the stock market. Two connections: they hire us, and we are still about 50% of their sales.

The stock market volatility should not happen, whatever is pro-cyclical to the stock market is making American labor inefficient as it copes with the financial connection. Swings in foreign terms of trade creep back into policy in DC, and DC is likely out of phase with managing this.

Why have we not learned to adapt to foreign financial volatility?