Zakaria: Democracy is decaying worldwide. America isn't immune.

The US Capitol dome is reflected in the glass roof of its underground visitor center ahead of President Barack Obama's first address to a joint session of congress, in Washington, February 24, 2009.  REUTERS/Jonathan Ernst   (UNITED STATES) (Newscom TagID: rtrlthree279529.jpg) [Photo via Newscom]

(CNN)A few weeks ago, the Economist Intelligence Unit published the 10th edition of its Democracy Index, a comprehensive ranking of nations that looks at 60 measures in five categories, ranging from electoral process to civil liberties. For the second consecutive year, the United States failed to make the top bracket of "full democracy" and was grouped in the second one, "flawed democracy."

It would be easy to focus on the state of American democracy under President Trump, but the more worrying aspect is that the United States' slide is part of a global trend. In this year's report, scores dropped for more than half the world's countries. What Stanford University professor Larry Diamond described 10 years ago as a "democratic recession" shows no sign of ending. The nature of this recession is perhaps best seen by looking at the state of the free press worldwide.