A large part of Statman's article is based on research by Edward McQuarrie who posts frequently here at Bogleheads. Excerpts from the article.
Excellent work Ed.Those investing exclusively in U.S. stocks during the centuries since 1792 have been relatively fortunate. When McQuarrie looked at international stock markets, in some cases he found losses over long holding periods of even greater magnitude than those he had identified in the U.S. Italian stocks, for example, lost 78.2% in the 20 years ended in 1979, Japanese stocks lost 64.3% in the 20 years ended in 2009 and Norwegian stocks lost 74.1% during the 30 years ended in 1978. Elsewhere, German stocks lost 21.5% in the 20 years ended in 1980 and Swiss stocks lost 20.9% during the 30 years ended in 1991.
Why do these international returns matter? First, many American investors hold international stocks for diversification purposes, so returns in overseas markets affect them directly. But second, and more important, U.S. stocks aren’t immune to the forces that hammered Italian, Japanese and German stocks, meaning declines of even greater magnitude are possible in the U.S. Just because they haven’t happened yet doesn’t mean they won’t.

Link to article - https://www.wsj.com/finance/stocks/stoc ... s-873723c1
BobK
PS - Statman was interviewed by Rick Ferri back in November.
Link to interview - viewtopic.php?t=443917