Joseph McCarthy's reign over America's political life was ferocious but relatively brief -- a mere four years, spanning his 1950 "enemies within" speech in Wheeling, W.Va., through his formal censure by the Senate in 1954. And the man most responsible for checking McCarthy's political power was President Dwight D. Eisenhower.

To many, Ike seemed unwilling or unable to denounce McCarthy. But in his new book, seasoned Eisenhower historian David A. Nichols sets out to correct the record. Drawing on "eyes-only" documents in the Eisenhower Library, Nichols adamantly maintains that unbeknownst to nearly everyone, Eisenhower and some discreet aides carried out a deliberate campaign against McCarthy.

On a personal level, Eisenhower despised McCarthy and his methods. The difficult question was: Where was McCarthy most vulnerable? The answer: Roy Cohn, the combative young lawyer on whom the senator heavily relied. Cohn, for his part, seemed infatuated with an unpaid consultant on McCarthy's Senate committee, David Schine, who was drafted into the Army in late 1953.

In a meeting on Jan. 21, 1954, in the office of Attorney General Herbert Brownell, top aides to Eisenhower decided to invoke executive privilege to keep Army officials from complying with McCarthy's subpoenas -- and to compile all of Cohn's strong-arm attempts to seek special privileges for Schine. That document, apparently two inches thick, was shown to journalists, including influential columnist Joseph Alsop. Bad enough that Cohn seemed to be targeting the Army to gain privileges for Schine; the unspoken implication was that the two were lovers. That may be why Eisenhower wanted to keep his distance from the attack on McCarthy.

The better-known blows -- Edward R. Murrow's critical broadcast, the televised Army-McCarthy hearings that climaxed in the famous "Have you no sense of decency?" barb -- were merely the culmination of the campaign. Indeed, the lawyer who asked that withering question of McCarthy, Joseph Welch, had been guided to the Senate committee, Nichols shows, by none other than Eisenhower himself.

Nichols has provided a gripping, detailed account of how the executive branch subtly but decisively defeated one of America's most dangerous demagogues.

James Ledbetter, editor of Inc. magazine, is the author of Unwarranted Influence: Dwight D. Eisenhower and the Military-Industrial Complex. This review originally appeared in the Washington Post.