All Marine Officers DO start out as infantry officers, at least they did when I went through TBS (The Basic School) in Quantico, VA. Then I went to flight school. The Marine Corps invests a lot by sending ALL officers (including lawyers, Academy grads, pilots, etc.) to 6 months training at TBS. They learn how to be a basic infantry officer then go to their MOS school.
Yes, they have since modified the course and now send the LTs who are going to be infantry officers on to the follow-on Infantry Officers School (IOS) which is even more rigorous.
Well then how does this woman be the first female in this course and yet there be female pilots?