Why is there no middle name field in U.S. visas? [closed]

U.S. visas have Given Name and Surname fields (see Google search for examples). The Given Name field might contain just a single name ("John") or multiple names ("John Michael"). But why is there no Middle Name field?

I'm asking because U.S. legal names consist of a first, middle and last name. When a U.S. visa holder with a given name consisting of multiple names ("John Michael") gets a U.S. legal name, it seems to be registered by the Social Security Administration as:

• First name: "John Michael"
• Middle name: none
• Last name: "Smith"

It would seem natural that "Michael" would be registered as the middle name, but the Social Security Administration insists that putting both "John" and "Michael" in the first name is the correct way to construct the U.S. legal name, based on how the name has been entered into the U.S. visa. And they will only register the U.S. legal name exactly as it is in the U.S. visa. But there does not seem to be any Middle Name field in U.S. visas. Why not?

The result is that foreigners with multiple given names face confusion and frustration when dealing with forms that require entering the U.S. legal name and associated Social Security Number, because most places do not expect the first name to consist of multiple names, while leaving the middle name empty. And it does not seem to be possible to fix this, because U.S. visas do not have a Middle Name field to move the rest of the given names to.