You can tell a great deal about Howard Blum's book by its cover. An American flag is emblazoned across its front with a swastika sewn over one of the stars, symbolizing the book's chilling underlying assumption - a full-blown Nazi conspiracy stitched right into the fabric of the republic.

Blum's text, at its best, is passionate in defense of the conspiracy theory - the notion that Odessa, or something like it, is active in the United States. The trouble is, it's paper-thin on all but circumstantial evidence and shot through with factual errors. Like its cover, Blum's book is an overstatement. Yes, there are Nazi war criminals living in America and it has taken the Justice Department a long time to move against them. Yes, a few of them were either well fixed economically or well plugged in politically. A couple undoubtedly did have CIA connections. But having said all that, one must fault Blum for not pointing out the two most likely reasons for the dearth of prosecutions over the last 25 years - lethargy and bureaucracy. And one must fault him for his careless reporting. How can a reader be expected to trust an author who on a single page tells us that the U.S. Marine landing in Lebanon was in 1956 instead of 1958 and that Robert McCloskey was U.S. ambassador to Argentina when he apparently meant Robert McClintock? (Quadrangle, $8.95)

Stephen Klaidman