The operational level is something that may be worthwhile in theory, but not in practice. I think examining all the linkages between setting national ends/ways/means (strategy if you like) all the way down to low-level actions (tactical, if you must) is well worth a lifetime of study and thought. Its useful to have definitions and categories for this theory and useful to argue about how all this interacts. For my part, I don't see "operational" as a "level" inserted between the strategy and tactics, but rather a connecting file or "nervous system" between national actions of setting goals and apportioning resources, and lower level concepts to use/arrange those resources to achieve the goals. Maybe its not operational, but rather “lower strategy,” or even “higher tactical.” I'm not sure, but I know there are connections and understanding the connections is critical to creating something coherent and effective.

"In practice", senior officials and commanders should not deal in terms of the theory, but in terms of the reality facing them. The theory can provide clues on the connections and considerations they should take into account. However, what is really important is the mission they are given, the resources they have, the environment they are in, the other actors they have to coordinate with, etc. Putting the levels of war into doctrine has led to many of the problems addressed in the SSI document such as commands either acting or failing to act based on their self-defined (or doctrine-defined) placement in the levels of war hierarchy. In my mind, the U.S. Navy has proceeded furthest in this area, to their detriment, by creating a table that aligns levels of war with specific command levels (NWP 3-32 Maritime Operations at the Operational Level of War). However, as identified in the SSI pub, other commands have used “operational level” as either excuse or justification to plan and execute outside of what the reality of their situation would recommend.
Phil Ridderhof USMC