In a self-governing country the people are called citizens. Under a despotism or autocracy the people are called subjects. This is because in a free country the people are themselves sovereign, while in a despotic country the people are under a sovereign. In the United States the people are all citizens, including its President. The rest of them are fellow citizens of the President. In Germany the people are all subjects of the Kaiser. They are not his fellow citizens, they are his subjects.
This is the essential difference between the United States and Germany, but the difference would vanish if we now submitted to the foolish or traitorous persons who endeavor to make it a crime to tell the truth about the Administration when the Administration is guilty of incompetence or other shortcomings. Such an endeavor is itself a crime against the nation. Those who take such an attitude are guilty of moral treason of a kind both abject and dangerous.

Theodore Roosevelt (1858–1919) American politician, statesman, conservationist, writer, US President (1901–1909)

Essay (1918-04-06), “Citizens or Subjects?” Kansas City Star
    (Source)

Regarding a bill which had just passed the Senate Judiciary Committee which would fine and imprison any one who used "contemptuous or slurring language about the President."

This passage was added to later editions of his essay, "Lincoln and Free Speech,", as printed in The Works of Theodore Roosevelt, vol. 21, The Great Adventure, ch. 7 (1925). It does not appear in the original version of the essay or book.