When battles were fought
With a chivalrous sense of should and ought,
In spirit men said,
"End we quick or dead,
Honour is some reward!
Let us fight fair -- for our own best or worst;
So, Gentlemen of the Guard,
Fire first!"

In the open they stood,
Man to man in his knightlihood:
They would not deign
To profit by a stain
On the honourable rules,
Knowing that practise perfidy no man durst
Who in the heroic schools
Was nurst.

But now, behold, what
Is war with those where honour is not!
Rama laments
Its dead innocents;
Herod howls: "Sly slaughter
Rules now! Let us, by modes once called accurst,
Overhead, under water,
Stab first."

Thomas Hardy

http://www.poemhunter.com/poem/then-and-now-2/