What does the brass mean, exactly, in military context

In books by many different authors I encountered phrases like this: He curses the brass for not caring whether he lives or dies. From context, it seemed to me that it meant high-rank officers

What Does GI Mean?

Brass Music Appreciation 1

Popular Musical Instruments of the 18th & 19th Centuries

What is meant by 'military brass' in a military context? - Quora

Fanfare trumpet - Wikipedia

Brass - Wikipedia

What is meant by 'military brass' in a military context? - Quora

Army Values: What Being A Soldier Is All About

A List of The U.S. Military Ranks in Order

What is meant by 'military brass' in a military context? - Quora

Russian general says top military brass betrayed soldiers fighting in Ukraine