A nice snippet from the Kenneth Branagh version of Henry V. Shakespeare's words are stirring:
We few, we happy few, we band of brothers;
For he to-day that sheds his blood with me
Shall be my brother; be he ne'er so vile,
This day shall gentle his condition:
And gentlemen in England now a-bed
Shall think themselves accursed they were not here,
And hold their manhoods cheap whiles any speaks
That fought with us upon Saint Crispin's day.
Somehow pacificism doesn't move hearts as martial virtues do. As George Orwell said, boys play with toy soldiers; toy pacifists will not do.
What was this battle all about? Who knows? A bit of France won by England, then won back. By all accounts, Henry V was a dunderhead. But so what? He still lives, and will, as long as Shakespeare is read and English is spoken.