The standard-of-identity laws are there for a reason. So here is my advice for the Dairy Industry: If you want to put artificial sweeteners in milk, just start calling your "milk-like drink" something else. Leave the "milk" label for the real stuff.
Little rumination is required to reach this conclusion: Cows don't make aspartame. But they don't make strawberry flavoring, either. This is relevant to a debate that involves a petition by the dairy industry to the FDA to change what qualifies as milk.