I have mentioned Elizabeth A. Marsland's excellent book before: "The Nation's Cause French, English and German Poetry of the First World War'. That book was first published in 1991 and has been re-issued now under the banner "Routledge Revivals" - further details www.routledge.com
On page 90 is a reference to 'patriotic poems' being printed and published 'as broadsheets' copied and reprinted from magazines and newspapers.
In particular the exploit of Elsie Mewis is cited. Elsie raised a huge amount of money for Belgian Refugees and Military Charities through selling a copy of a poem she wrote and had printed. A poet and an inspirational women - but there were many of those!
Anyway, the point is that gave me an idea. I am often being asked to suggest publishers and there are many of note who do publish anthologies of poetry. However, if you keep receiving rejection notices, my advice is to publish your work yourself.
This is the age of the Internet and Kindle and there is plenty of advice available on how to 'self publish'.
And you could perhaps link up with and donate a few pence per copy to one of the amazing military charities there are now - e.g. Hounds for Heroes, Soldiers off the Streets, the Royal British Legion, The Army Benevolent Fund, The Royal Air Force Association, Combat Stress, Help for Heroes - I haven't found a Royal Navy charity yet but am every hopeful - to name but a few.
Just a thought. Just do it!