Let's start from the beginning. While the 1920s was a period of global economic expansion and globalization, it also led to rising inequality. The US experienced a marked increase in stock prices and such asset price booms usually tend to favor the rich. The party then suddenly came to an abrupt end in 1929 with the famous stock market crash, which was partially engineered by the Federal Reserve as policy makers became increasingly worried about elevated asset prices.
The early 1930s were characterized by the Great Depression. The asset price crash sparked financial crises not only in the US but also in continental Europe, especially Austria and Germany. Policy makers exacerbated the economic downturn with senseless austerity measures, which contributed to the decline in spending and aggregate demand. Monetary policy was of course constrained by the gold standard. The countries that left the gold standard early and depreciated their currency recovered much more quickly from the downturn whilst countries that maintained their peg to gold experienced the strongest economic decline. And unemployment led to the rise of populism, especially in Central Europe. Officials increasingly resorted to populist measures, such as raising tariffs on imported goods in order to protect domestic industries. This sparked a trade war, which only exacerbated the downturn. Last but not least, voters in one large advanced economy electeded a racist and antisemite into office.
It should be clear to everybody right now that the last decade or so has been almost a one to one repeat of the 1930s. We had a period of rapid globalization combined with spectacular asset price increases, especially in the U.S., followed by a global financial crisis and a worldwide recession across advanced economies.
While policy makers largely did not repeat all the mistakes that were made in the 1930s, it is abundantly clear that advanced economies did not perform very well over the last 10 years. Austerity policies did a lot of damage and Central Bankers were largely much too timid in pursuing aggressive monetary policies that could stimulate the economy and push unemployment back down to more normal levels. As a result, we have seen a rise in populism and fascism, not only in the US where it culminated in the election of Donald Trump, but also in Europe. Let's not deny it, we now face a situation where a fascist is sitting in the Oval Office. So, by large, the last decade has been almost a one to one repeat of the 1930s, which culminated in the election of a fascist leader in Nazi Germany and subsequently World War II.
Obviously, we are not quite there yet, but recent tensions with North Korea and Russia do not exactly bode well for the future...