I don't see a reason why you couldn't do your time in the army and later become a journalist, not sure how what major you could choose though.
2019 WestPoint class appointee
Recipient of 4 year army rotc scholarship.
"Journalism? You think you're Mickey Spillane? Do you think you're some kind of writer?"
Hey guys, I want to be a journalist or screenwriter. Would you recommend going to USMA? Becoming an officer is a personal goal of mine, but I ultimately want a writing career.