Say you're attacked by Martians. They're little green men, they're acting aggressively, and there's a large red "M" on the side of their spaceship.
It would be normal for you to defend yourself.
You've seen War of the Worlds. So you fight. And you lose. Or maybe you win and go "whew!"
Later, amidst the carnage of battle, you discover they aren't Martians at all. They're from the planet Maloomba.
And that aggressive behavior you observed was not aggressiveness -- it's normal conduct on their planet as they go about daily life. What looked like weapons are tools they use to survive and do their work. To them, you attacked first.
They aren't for you, they aren't against you. They're just being who they are.
But you didn't know any of that
You only had your own limited judgment, perspective, and experience. And you put total confidence in it.
You'll react differently the next time little green men in a spaceship with an "M" on the side appear. Your perspective has changed.
And in a lot of other ways you might decide to be a little more cautious about jumping to conclusions.
Choose yours with patience and humility. Get all the help you can to make sure you know what you're seeing.
Save your energy for the real battles. There will always be plenty.