You will find yourself in situations where flight rather than fight is the option. Sometimes its hard to tell. And the fighter in you will say - "Don't be a wimp, don't give in, show them what you are made of."
But its plain silly to act that way all the time.
Knowing what to do - takes experience and maturity. It also helps if you are able to make the decision coolly, keeping down as much of your emotion as possible.
Yet at the same time- appeasing bullies - is totally counterproductive too. The more you give in, the more they demand.
When Hitler rose to power in 1933, everyone thought they could work with the bastard. Work it out. Lets find a win-win solution. So they let him break the Treaties, then they let him rearm, they they allowed him to forcefully incorporate other nations into Germany : Austria, Czechoslovakia (bite by bite), by the time they realized they had to fight Hitler- it was too late. He was too powerful- he was no longer an easy target.
Sometimes the battle is not winnable at all. My ancestors came from China- my great-grandfather took part in an uprising against the Manchus. He was a pastor, scholar and also a rebel. They lost. If he had continued his fight- he and his whole family would have caught and executed.
There's a difference between foresight and hindsight. Its always easy knowing what to do after the event- its another to make a good decision regarding the future.