The modern military and throughout military history, saluting a higher ranking officer is a sign of utmost respect. Only two officers of equal or almost equal rank can call each by their first name.

In my story characters salute any officers of higher rank even though that officer maybe of a different gender, religious background, species etc.

Ex: A marine recruit sees a female officer walking towards him, he salutes her, because it shows her respect. The female officer returns the salute as she passes. Regardless of the recruits views on women he can not refuse to salute an officer.

Thoughts firmbeleiver?

An officer is an officer regardless what gender and commands respect from lower ranked military personnel.