Frederic Bastiat  is often credited with having said something like "If goods don’t cross borders, soldiers will." Bastiat almost certainly believed these words to be true, but I can find no evidence that Bastiat really did write such a thing. (I’m happy to be corrected.)
But on page 255 of Jeffry Frieden’s Global Capitalism  (2006) I find the following: "As one of [FDR’s Secretary of State Cordell] Hull’s supporters put it, ‘If soldiers are not to cross international borders, goods must do so.’"
Frieden’s footnote to the above sentence attributes these words to one Otto Maller, and gives a citation to page 37 of Alfred E. Eckes, A Search for Solvency: Bretton Woods and the International Monetary System, 1941-1971  (1975).
I can find nothing about this Otto Maller; Googling that name produces a mere five hits, none of which seem to point to the person referred to above.