Turn your clock back 70 years. Imagine that Wall Street banks and brokerages sold Nuremberg-compliant bonds and stock funds in 1938. American Nazi sympathizers bought financial instruments certified by Berlin-based advisors as free of “Jewish profits” from, say, Salomon Brothers and Bloomingdale’s. In turn, a percentage of such funds’ gains underwrote pro-Nazi charities, like the German-American Bund, and similar organizations in the Fatherland, like the Hitler Youth. Seventy years hence, an analogous outrage grows on Wall Street, only this time for real. Sharia-compliant finance (SCF) is expanding among banks and securities houses eager to absorb the hundreds of billions of...