Huh? 9mm Parabellum (9mm Luger) has been used with moon clips. AFAIK the first such use was by Israel in their copy of the S&W M&P, which used half-moon clips the same way as the U.S. Model 1917 revolvers.
The main reason S&W tried their 9mm revolver was that a foreign police agency wanted to continue to use revolvers for PR reasons, but wanted to get free ammo from the army, which used 9mm. They didn't want to use moon clips. So S&W tried and the guns worked but it was not an elegant solution.
I doubt that there is much of a U.S. market today for a 9mm revolver. The old cops who were married to their revolvers are about gone and the younger generation happily go with 9mm autos.