The opinions of the young are greatly appreciated and encouraged. However, you need to realize that those that differ from you are very valueable because seeing both sides of an issue can either change your opinion some, or make your current resolve even stronger. Either way, don't scare off those that differ from you. If you are too negative, they might not even respond back, and that would not do you any good.
Keep caring and get involved, it's your world and future.