The core of war poetry is war. As long as it is related to war, it can be called "war poetry".
The core of frontier fortress poetry is frontier fortress, and any poem related to frontier fortress can be regarded as frontier fortress poetry.
The concepts of war poems and frontier poems are most easily confused, because they overlap with most poems, but some poems belong to only one of them. For example, some poems describing the scenery beyond the Great Wall can be counted as frontier poems, but not as war poems.
Other kinds are quite different from war poems.
Military poems mainly reflect the thoughts and feelings of military life and some military careers.
Obviously, patriotic poems can be counted as patriotic poems as long as they express patriotic feelings. After all, not all expressions of patriotism are related to war.
The same is true of poems about garrison, which can be called garrison poems.