Toward Ecosophy

Good heavens, yes. Practitioners of evil magic have to depend on the ignorance and lack of skill of their targets. Most attacking spells can be shredded by ordinary protective rituals or natural magic methods. If the target has some experience with meditation and subtle energy work, for that matter, he can learn how to redirect the energy of attacking spells for his own uses -- this isn't especially difficult, though it takes some subtlety.