Is fear rational?

I fear failure, while other people think failure is just apart of the road to success. What we fear is not rational, but what we fear is real. If you don't fear anything, you walk right out in front of moving traffic. Sometimes fear keeps you safe, but other times fear keeps you from taking chances. So who decides what fear is rational, and what fear is not? Too much of it is a bad thing, yet too little isn't good either. Fear makes you afraid of losing something or someone. It's what keeps you honest, when every fiber of your being is telling you to lie. I think the people who fear clowns or spiders don't know real fear. I think that fear is something that comes when you feel like you have nothing left so you are afraid. A clown isn't scary, but losing someone close to you is. Having your dad in the military stationed somewhere far away from you is something to fear, not going into a haunted house with a group of your friends. Are my fears rational? To me, yes. My fears are what keep me on the right track. They help me to take chances that I normally would talk myself out of. I'm afraid of failure, therefore I don't accept it in any aspect. I fear perfection, because I know no one is ever truly perfect even though I strive to be on a regular basis. I fear that I'll never be good enough or that someone will always be better. Some fear fuels you, and some fear tears you down inside making you feel weak. You decide what you fear, but you also decide whether or not you let it rule your life. I let what I value most deserve my fear. My family, my friends, and my future are all things that hold my fear. I don't think silly things deserve our fear, but I think things that matter most to us do.