Yup, already knew that. The problem is I never have backup troops. I send all to war
Defending territory which does not need to be defended is usually a drain on troops that you may need elsewhere.
For example, having 1 AFV + 2 Inf in every homeland city despite the enemies your fighting being on an entirely different continent. This isn’t really needed as those troops aren’t doing anything defending unlikely attack locations while they could be scoring kills in enemy territory.
Of course, you most likely knew that already, I was just throwing it out.