Amity Shlaes' timing couldn't be better. With the Party of Lincoln facing its biggest crisis since the Nixon resignation, the senior fellow at the George W. Bush Presidential Center has come out with an exhaustive, 576-page biography of a Republican who helped his party win three presidential landslides during the Roaring Twenties: Calvin Coolidge.

In "Coolidge," Shlaes not only performs the heavy lifting to bring this remarkably effective president out of obscurity. The economist-turned-historian also makes a compelling case that the "Silent Cal" of the 1920s -- a modest man who never felt at home in Washington -- offers hope for both party and country in the 2010s. She's right about that, but not for her stated reasons.

All Republicans can agree with the Bush Center scholar that Coolidge represents a lost pearl. Indeed, Shlaes' narrative vindicates the 30th president against the attacks of the political Left, which is quick to blame him for the Depression. She captures the essence of a decent and ordinary New Englander who inherited a Puritan devotion to thrift, service, work, fairness and integrity. As demonstrated by his decision not to seek his certain 1928 re-election, Coolidge was the anti-politician: restrained in both speech and action but always delivering more than he promised. Called more than driven, his rise to power surprised the political class but was facilitated by average Americans, who trusted him as one of their own.

Not all will salute how Shlaes nuances her subject. Like Leo Strauss fans who read American history selectively, this alumna of the Wall Street Journal editorial board hears from Coolidge what she wants to hear. Because he persevered against all odds to cut tax rates, reduce spending and pay down debt, Shlaes positions Coolidge as a poster boy for typical libertarian demands for tax cuts for investors, fiscal austerity, unfettered free trade and open borders.

But the silent president's own words put him more in league with the populist Pat Buchanan. Like Pat, Coolidge spoke of and believed in "Americanism." He cared deeply about the "silent majority" -- a phrase coined by Bruce Barton, a college buddy -- while dismissing elite cranks like Sinclair Lewis who disdained churchgoing, socially conservative Americans like himself. And he defended modest tariffs and tight borders as pillars of good jobs for American citizens.

Although she laments that Coolidge never adopted the free-trade dogma of another lifelong friend and J.P. Morgan partner, Dwight Morrow, Shlaes skirts how Coolidge's position on tariffs and borders does not easily fit into the libertarian playbook. To her frustration, Coolidge remained in the protectionist tradition of Hamilton, Clay, Lincoln and Theodore Roosevelt.

Shlaes has even less to say about Coolidge's signature on the Johnson-Reed Act of 1924 -- legislation that restricted immigration until 1965 -- preferring to emphasize that Coolidge defended the civil rights of immigrants already naturalized. Perhaps unknowingly, she casts Coolidge as a precursor of Samuel Huntington, the late Harvard historian and patriot who believed that immigrants must master English and assimilate into a settled American culture.

The author also ignores the contrast between Coolidge's "minimalist" foreign policy and the interventionist model of the 43rd president. Coolidge's final triumph was the Senate-ratified 1928 Pact of Paris, a multinational agreement not to use "war as an instrument of national policy."

To be sure, transplanting any historical figure, especially the one-of-a-kind Coolidge, into today's political environment is tricky. But this great president who bolstered the GOP brand was neither a neoconservative nor a libertarian. Coolidge's one-nation conservatism instead offers an anchor for a party adrift.

Robert W. Patterson, a veteran of the George W. Bush administration, recently served as a welfare adviser in the administration of Tom Corbett, governor of Pennsylvania.