As scholars who study the death of democracies around the globe, Steven Levitsky and Daniel Ziblatt saw Donald Trump's rise to power as an alarming sign of dangerous times ahead for the United States.
The two professors of government at Harvard University found parallels with fascism in Germany and Italy before World War II and with Latin America's long struggle with dictatorships.
In the United States, they argue in their new book, "How Democracies Die," the threat comes not from a military coup, but from a duly elected leader who, like former Venezuelan President Hugo Chavez, subverts democratic institutions one step at a time in a steady march to autocracy.
"We must be aware of the fateful missteps that have wrecked other democracies," they write.
It's an offensive argument to many Trump supporters, who welcome the president's shattering of tradition in Washington.
Levitsky, however, said Trump's latest efforts to undercut the criminal investigation of his campaign's ties to Russia only buttress the case that the president is imperiling U.S. democracy. Here are excerpts from an interview with Levitsky.
Q: What do you make of Trump's demand for loyalty from the attorney general and FBI leaders?
A: It's difficult to think of an elected autocrat who did not try to bring what we call the referees -- law enforcement, intelligence and judicial agencies -- under their control. These agencies (then) serve as a shield so that the government cannot effectively be investigated or prosecuted.
Law enforcement agencies, intelligence agencies and the courts in most democracies are at least supposed to be independent, neutral arbiters. They are not supposed to play on the government's side. In many politicized, weak or failing democracies, you see governments exert varying degrees of control over the referees.
Q: You see Trump as a threat to American democracy?