(His election is possible but still unlikely, because the Democrats have an intrinsic advantage on the electoral college map, and President Obama's approval rating has begun to exceed fifty percent, traditionally a key determiner for the outcome of the election of a president's successor.) But what would the world look like if Donald Trump actually became president?

Trump has threatened to pull out of the NATO alliance in Europe and withdraw troops from Japan and South Korea if these countries don't pay up, and remove the U.S. nuclear umbrella from those two nations. (If the United States withdrew from NATO, the US nuclear shield would also stop protecting European NATO members.) Instead, Trump has spoken of having better relations with the nuclear great powers of Russia and China.