In the beginning, my son was considering going to medical school. That was one of his options before accepting the academy. So at the academy, he took the normal pre-req type classes for medical school. Organic chemistry, anatomy, etc. In the process, he started taking psych/soci/anth/type classes and realized he liked behavioral science. So he kept the option open for medical school in the area of Psychiatry. But probably into his 3rd year at the academy, he still liked the idea of flying. And because the academy/air force doesn't care what a pilot's major is in, he stayed with behavioral science major. Unfortunately, there are very few master's programs in behavioral science. Most people in that field get into counseling and similar areas. They usually have just a bachelor's degree or they go for a PhD. Only one option for grad school out of the academy would accept a behavioral science major for grad school. Fortunately, that was the RAND; and they offered him a 3 year PhD program which he accepted.
Now; during that PhD program, he had a change of heart about remaining on the path to be a pilot. He had always wanted being a Special Tactics Officer; but until then, I think he was playing it "SAFE" with the pilot slot. But he made up his mind and tried out for selection for the STO career. And after he passed selection, he was interviewed. And the question came up from the board interviewing him. "Why does an officer, with a Bachelor's, Master's, and PhD want to be in Special Operations; and how does degrees in Behavioral Science and Policy Analysis help Special Ops"? He mentioned that his PhD Dissertation was on PTSD; as was his research for his Bachelor's. He felt he could help the fellow airmen, soldiers, and sailors in special ops with PTSD type issues related to the job. Plus; his PhD in Policy Analysis prepared him for how to work within the system to get the resources his team/squadron needs to succeed in their mission. Apparently the Colonel and the rest of the review board liked his answers and believed he would be an asset to the Special Operations Command.
But you have to realize that special operations isn't something you just decide you want and you ask for it. It's one of the few careers where you actually have to go through a selection process. Intense basic training type environment. Mental, Physical, etc. The selection starts with many applying. Out of those, they will select about 27-28 to come to selection. Of those, about half or over will quit, drop out, or be released. About 12 will actually make it through selection. Then, of those 12, after interviews and boards, they will select about 5 to actually become part of the Special Ops program. Of the officers who become Special Tactics Officers; there is ONLY about 80-85 of them in the air force. The others not selected, go back to what they were doing. Of those selected, they have all sorts of majors from the academy or college. Physics, History, Behavioral Science, Management, etc. But just like they asked my son, they would ask you how does your training and education benefit Special Ops. So no, his major didn't matter. But how he APPLIES that major to the program would.
That would be the same with any type of major. Of course, like I mentioned previously, there are some jobs that must have a certain major. Meteorologist probably needs more than an English Degree. Electrical Engineer probably won't get that job with a History degree. Also, except for pilot, they do take into consideration your major in giving you your job. I.e. A person with a business/financial/etc. type degree might have a better chance at getting a job in Acquisitions, contracting, financial services, etc. than an individual wanting the same job and had a degree in chemistry. Not that they can't get that job; just that if they think you have a natural disposition for the job, based on your education, that will definitely help.