Use the date default format of the users device.
The only nation in the world that uses the American date format is... you guessed it; America. (OK, so maybe some islands in Micronesia and the Marshall Islands too.) That's about 325 million people.
The vast majority of the rest of the world uses the DMY date format, or approximately 3,700 million people. That's about 12:1.
Please let us set our preferred date format.