Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Researcher uncovers truth behind wartime security slur

San Diego

Austrian-born oceanographer Walter Munk has never forgotten the false allegations of Nazi sympathies that prompted the US government to strip him and his mentor of their security clearances six decades ago.

A disclosure of government files has now confirmed the thinness of the case prepared against the two by J. Edgar Hoover, director of the Federal Bureau of Investigation (FBI).

Munk is keen to tell his story to today's scientists — some of whom may also find their loyalties questioned on the basis of their ethnic origins. He has recently published an account of the events (Oceanography 15, No. 4, 7; 2002), after obtaining his case files under a Freedom of Information Act request.

Munk and his Norwegian mentor, Harald Sverdrup, lost their clearances in 1942, while working at the Scripps Institution of Oceanography (SIO) in La Jolla, California. The duo was involved in a wave-prediction model that was crucial in aiding the US Navy's first amphibious landing of the war in North Africa.

Sverdrup, a prominent Norwegian oceanographer who was the SIO's director from 1936 to 1948, never again received full security clearance, although he acted as a government consultant on military projects. He died in Norway in 1957, never knowing why his clearance had been withdrawn.

Munk, now aged 85, won back his military security clearance soon after it was pulled — helped by leading scientists who wrote to the government on behalf of the duo — and is still a senior SIO researcher.

Records held by the Navy and FBI show that the clearances were withdrawn as a result of statements from two now-dead faculty colleagues at Scripps — bacteriologist Claude ZoBell and biochemist Denis Fox — and of some other acquaintances.

Munk and Naomi Oreskes, an Earth-science historian at Scripps who has also written about the affair, believe that the investigation may have been driven by grudges arising from Sverdrup's leadership of Scripps. There was no evidence of Nazi collaboration or misdeeds in the files, only records of the informants' testimony, possibly based on the fact that the two were foreign and spoke German.

Munk was “amazed” on reading the sum of the evidence against him and Sverdrup, he says. The investigating agencies “deprived the country of needed talents and put the careers of several individuals in jeopardy”, Munk writes in his article.

Oreskes and Ronald Rainger, a historian at Texas Tech University in Lubbock, asserted in an article on the affair (Stud. Hist. Phil. Mod. Phys. 31, 309–369; 2000) that the probe helped to create a framework for subsequent government investigations of physicists, including Robert Oppenheimer, engaged in the Manhattan Project to build the atom bomb. “In matters of loyalty, the burden of proof was on the accused, not the accuser,” they say.


Rights and permissions

Reprints and Permissions

About this article

Cite this article

Dalton, R. Researcher uncovers truth behind wartime security slur. Nature 421, 303 (2003).

Download citation


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing