Conrad Black is the author of Franklin Delano Roosevelt: Champion of Freedom, Richard M. Nixon: A Life in Full, A Matter of Principle, and the recently published Flight of the Eagle: The Grand Strategies That Brought America from Colonial Dependence to World Leadership. He can be reached at cbletters@gmail.com.

The United States, viewed from outside, is almost sleepwalking into a post-American world, with practically no audible awareness that this is happening. It may be that the media and government of the country are now so completely in the hands of people who think America’s prominence in the world is a bad thing, or think that a retreat to America will release more resources for addressing domestic problems, that a general retreat of the U.S. in the world is not judged newsworthy. More vigilant and traditionally patriotic and optimistic Americans dissent from this silence, and they also largely refrain from the ceaseless mantras about America’s greatest years’ being ahead of it (even though, as Marco Rubio and others assert, it has long been “the greatest country in human history”).

One of the observers most sensitive to the constant evidences of this decline is Peggy Noonan, the blithe spirit and fine wordsmith who was once Ronald Reagan’s speechwriter, and writes now in the Wall Street Journal. Her column on June 1 was headed “An Antidote to Cynicism Poisoning.” She again deplored the disgraceful abandonment of the besieged consulate in Benghazi, which cost the lives of the ambassador and three of his officials, and she was annoyed by the fraudulent pretense that it wasn’t a terrorist operation but merely a response to a cranky video from a freelance American critic of Islam. She deplores the official harassment of various media critics of the Obama regime. But Peggy Noonan is truly and sensibly appalled most particularly at the conduct of the IRS.

Ms. Noonan brushes aside the feeble sophistries that presidents have often used the IRS to harass opponents; the current revelations are of especially widespread misconduct, and officials of the IRS have lied to Congress and have exercised their right to silence in unusually suspicious ways. What occurred in 2012, she correctly remarked, was that a Democratic president used the Democratic political clerisy to reelect himself in a corrupt abuse of the system, followed by a glazed pall and indifferent shrug of ignorance and prevarication. The president claimed to know nothing....