?I admire Russia for wiping out an economic system which permitted a handful of rich to exploit and beat gold from the millions of plain people... As one who believes in freedom and democracy for all, I honor the Red nation.? ?FRANK MARSHALL DAVIS, 1947

In his memoir, Barack Obama omits the full name of his mentor, simply calling him ?Frank.? Now, the truth is out: Never has a figure as deeply troubling and controversial as Frank Marshall Davis had such an impact on the development of an American president.

Although other radical influences on Obama, from Jeremiah Wright to Bill Ayers, have been scrutinized, the public knows little about Davis, a card-carrying member of the Communist Party USA, cited by the Associated Press as an ?important influence? on Obama, one whom he ?looked to? not merely for ?advice on living? but as a ?father? figure.

Aided by access to explosive declassified FBI files, Soviet archives, and Davis's original newspaper columns, Paul Kengor explores how Obama sought out Davis and how Davis found in Obama an impressionable young man, one susceptible to Davis's worldview that opposed American policy and traditional values while praising communist regimes. Kengor sees remnants of this worldview in Obama's early life and even, ultimately, his presidency.

Is Obama working to fulfill the dreams of Frank Marshall Davis? That question has been impossible to answer, since Davis's writings and relationship with Obama have either been deliberately obscured or dismissed as irrelevant. With Paul Kengor's The Communist, Americans can finally weigh the evidence and decide for themselves.