I'm looking for a specific war poem...

[hotchoc]

I believe it contains both the lines "how sweet and good it is to die for one's country" and something about "when you get back please tell them". I can find the Wilfred Owen poem which contains a very similar first line but no reference to the other line.

[Leo-Bloom]

'Dulce et decorum est pro patria morte' is the Latin line which translates as 'How sweet and fitting it is to die for ones country'
I can't think of another poem apart from Owen's which contains that line.
It was originally written by the Roman poet, Horace.

[Pentalpha8]

Apart from Leo-Bloom's suggestion of the first line you mention I can only think of the lines ,
When you go home, tell them of us and say ,for your tomorrow we gave our today which is known as the the Kohima poem by John Maxwell Edmonds .

[fairkatrina]

Ducle et decorum est' is an anti-war poem, making the point that the notion that it is good to die for patrotism is a stupid one; he calls the philisophy of 'dulce et decorum est' '"that old lie" following the graphic description of a man's death by poisonous gas. it is also the last line of the poem, not the first. the last verse reads:

If you could hear, at every jolt, the blood
Come gargling from the froth-corrupted lungs
Obscene as cancer, bitter as the cud
Of vile, incurable sores on innocent tongues,
My friend, you would not tell with such high zest
To children ardent for some desperate glory
That old lie: Dulce et decorum est
Pro patria mori.