War in a dream: what does it mean?
For a great many dreamers this is not a symbol, and a dictionary should say so before it says anything else.
How do the four traditions read it?
Each reading below comes from a named tradition and a cited source, so you can see where it came from and decide what fits your dream. The four often disagree, and that is the point: a symbol rarely means one fixed thing, and the distance between Freud, Jung, modern research and myth tells you more than any single verdict could.
Freud
Freud lived through the First World War, treated soldiers afterwards, and revised his account of dreams because of what he saw: the repetitive traumatic dream did not fit a theory built on wish, and he said so.
After Freud, The Interpretation of Dreams (Brill trans., 1913), public domain.Jung
A Jungian reading might take conflict in a dream as internal where the dreamer has no experience of war, and would be careful not to offer that reading to somebody for whom the dream is memory.
Our summary of a Jungian reading, in our own words, not Jung's. See Jung, ed., Man and His Symbols (1964).Modern
Repetitive dreams that replay a real event are a recognised feature of post-traumatic stress and are different in kind from ordinary nightmares: they change little, they wake the sleeper, and they do not respond to reassurance. Effective treatments exist, including imagery rehearsal therapy and trauma-focused talking therapies, and asking for them is an ordinary thing to do rather than a last resort.
Our summary of the threat-simulation position. See Revonsuo, The reinterpretation of dreams (2000).Mythological
Every generation has believed its war would be the last, and the phrase about a war to end war was in circulation before the fighting it named had finished. What survives longest in the accounts is not the battles but the waiting.
Rosmerta Publishing editorial synthesis. Our own words; no quoted text.How can writers use this symbol?
The same symbol, read as craft material rather than as a dream. What it does on the page, how genres use it differently, and what happens when you turn it inside out. Written for novelists, screenwriters and poets who need the symbol to actually work, and it ends with something to try.
In literature
The waiting is what veterans describe and what fiction leaves out, and the accounts that convince are almost always about boredom interrupted rather than action sustained.
Rosmerta Publishing editorial synthesis. Our own words; no quoted text.What it does in a story
The thing that is not a symbol to everybody.
Genre conventions
Established in a montage, and used as a backdrop for a romance.
How to subvert it
Write the waiting, at length, and let nothing happen.
Try this
Two hundred words about a long period in which nothing happens and everybody is afraid.
Only the first of these names a source. What a symbol does in a story, how genres treat it, how to invert it and what to try are our editorial judgement as writers and editors, not findings from a body of research. They are offered as craft opinion and should be argued with.