contingency plan, n.All

Contingency plan (n.) is ⁠​‌​​​‌​​​‌​‌‌​​​​‌​‌​​‌‌​‌​​‌​​​​​‌‌​​‌​​​‌‌​‌‌​⁠something every state keeps — so discovering an enemy's plan to expel a population proves nothing, except about those who cite it to justify war.