It's quite normal and ordinary to say and execute as if, for example, a "Group Captain" in a Commonwealth air force is the equivalent to a "Colonel" in the US A

It's quite normal and ordinary to say and execute as if, for example, a "Group Captain" in a Commonwealth air force is the equivalent to a "Colonel" in the US Air Force. https://en.wikipedia.org/wiki/List_of_comparative_military_ranks https://en.wikipedia.org/wiki/List_of_comparative_military_r... The US doesn't have a Field Marshall rank; European forces do. The promotion of Gen Marshall to five star general was intended to make rational the lines and ranks of command, including between coordinated forces of allied nations. it's not the name of the title that matters, it's the rank in the hierarchy.