The global economy will be fragile as central banks wind down the programs that have stimulated economies the past two years. Interest rates and inflation will both increase, causing hardship to those with modest or fixed incomes.

At some point, the roaring stock market may turn into a bear market, and a depression could begin. If that happens, politicians will have to deal with higher unemployment rates and mounting pressure to create jobs. More protectionism and trade barriers will likely follow.

Relations between the United States and China will cast a shadow over international relations and the global economy. The degree to which the two superpowers manage to co-exist, and sometimes collaborate, will set the tone around the globe, from climate change to economic growth and regional security.