There were two key officials with whom Jean Monnet worked closely during the Roosevelt Administration, Harry L. Hopkins, Presidential Aide and Henry Morgenthau, Secretary of the Treasury, but he had very different relationships with both men. Morgenthau had an innate distrust and suspicion of international investment bankers and in 1938 when Monnet arrived in Washington to purchase aircraft on behalf of the French, he was still involved in banking. So besides the problems Monnet experienced with the US in purchasing planes, because of the Neutrality Act and because of a strong political lobby favouring isolationism, Monnet also had to deal with Morgenthau's suspicions. At the time the Treasury Dept. had a procurement division which dealt with war purchases until the enactment of Lend-Lease, so Morgenthau was co-ordinator for all arms sold to France and GB until 1941. While Morgenthau disagreed with Monnet's plans for aircraft factories to supply the French to be built in Canada he was one of the key officials to kick-startAmerican concerns about Nazi Germany and to support French re-armament. After the fall of France, Monnet became involved with the British Supply Council in Washington, but Morgenthau still deeply sceptical about Monnet went to the British Ambassador Halifax and the British Minister for Production Oliver Lyttleton regarding his objections to Monnet because of past business deals with German Corporations. Furthermore, Morgenthau initiated an investigation into Monnet's business partnership with George Murnane regarding allegations of hiding German ownership of companies from the US Government, particulary with reference to American Bosch. This investigation was followed by a tax investigation in 1943. It is thanks to Monnet's many supporters that he did not loose respect in Whitehall and Washington. Yet despite Morgenthau's doubts about Monnet's allegiances, he and Monnet were able to get on with the business in hand and to co-operate in arming Europe.

The originals are held in various Archives and Presidential Libraries in the USA