The Tao Te Ching has several verses that address the nature of conflict between peoples and nations. Below are a couple of these passages from the modern interpretation by Ralph Alan Dale:
Verse 68
The best soldier fights
without vengeance,
without anger
and without hate.
He puts himself humbly
below his comrades,
thereby eliciting
the highest loyalty from them.
This is the power of non-belligerence
and cooperation.
It is the ancient path to the Great Integrity [Tao].
Verse 69
There is a saying among those wise in military affairs:
“We do not act as hosts taking initiative,
but would rather be the guest assuming the defensive posture.
Rather than advancing one inch,
we would rather retreat one foot.”
This is called advancing without moving,
rolling up one’s sleeves without baring one’s arms,
fighting without weapons,
capturing the enemy without attacking.
There is no greater disaster
than boasting of one’s invincilbility.
Such boasts lead to the loss of the Three Treasures.
[note: the Three Treasures, from Verse 67, are love, moderation, and humility]
Therefore, when two opposing sides meet in battle,
the one without an enemy
will be victorious.