It is one thing to be called up to defend your country against physical attack.
The doctor put up his hands as if to defend himself against physical attack.
"A man must always be prepared to defend himself against attack."
Today national security means more than defending against military attacks.
Sometimes you need to be attacked in order to learn how to defend against future attacks.
But remember, the main purpose of the escort is to defend you against attack.
The 9th was not engaged in the following days of the battle, except to defend against attack on 20 May.
They apparently have the need and justification to defend themselves against attack.
Such information could help prepare for an offensive, not just to defend against attack.
In 1781 it was defended against Indian attack and them abandoned.