War. 24/7. That's what should be on your mind if you want to become King or Queen Shmoopton the Third. Stop thinking about war, and you're as good as done.
Oh, and if you don't even have an army, you're just pathetic. There's no sugar-coating it.
Think about peace as war prep-time. During this time, a ruler should exercise and train his troops. He should also think about everything possible concerning war and read history to look at examples of other rulers' war strategies, just like football players study playbooks.
Basically, make sure you get ready for war before it happens, or you'll be sorry.