Clyde also got into a drug war with Victor over control of the apparently lucrative drug trade in Salem, and had Sonny stabbed in the back as a warning to Victor to stay out of it or he would start going after all of Victor's loved ones. Victor knows that Clyde was responsible for Sonny almost dying, but this man who pledges his entire life for his family never did anything about it. And Sonny to this day does not know who stabbed him.