It requires education, but not necessarily schooling.
My friend's father worked on some later Apollo missions and ended up leading a Titan engineering group with no college degree. He was a damned good engineer, though. If it were possible to earn mathematics degrees by test taking, he'd easily have had a graduate degree.
In the beginning he was a technician (which didn't require a degree), and once during crunch time he literally fixed a buggy electrical component an engineer was showing to his boss in front of his eyes. In his words after that one lucky break, he never looked back and just kept working his way up, excelling and proving himself in each position. After a point, the fact that he had no degree made his managers take more notice of him. Clearly a man who had to work his way up through several levels he wasn't supposed to be eligible for had something unique.
It's difficult, especially in the defense industry, but sometimes talent wins out over credentials.
Funny. That is totally different in Europe. Engineering very much requires higher education, which definitely includes at least a basic understanding of business, economics, law etc. and of course good knowledge of physics, mathematics and deep insight in some engineering field.
This is usually taught as a bachelor's degree. (Bachelor of Engineering)
That said, there are some able men and women who carry out engineering jobs without a degree (even though IIRC they can not call themselves engineers)
I was referring only to US tendencies to perceive certain professions as more prestigious. Doctors and lawyers have more prestige compared to other professions if you only include those prestigious professions that mandate higher education.
You are getting close: List the characteristics of the usual professions and then conclude that in the US software is not a profession. It's even less of a profession than being a plumber or electrician since can need a license for each of these.
Lawyers? They have a cute professional rule that a lawyer working as a lawyer must be supervised by a lawyer. So, no stuffed suit, business middle manager types need apply to supervise lawyers in an organization.
