"Straight Edge" is a song written by Minor Threat in 1981. The song talks about not drinking alcohol or smoking or using "a crutch." It was a personal statement but one that quickly became a philosophy. Star Wars is a sci-fi franchise that was created by director George Lucas in 1977. The two have very little to do with each other, in fact in terms of actual overlap between the two there is none. Luke Skywalker says nothing about hardcore and Ian MacKaye says nothing about intergalactic disputes. That being said, there's plenty of people who find enjoyment in both, and some people who even try to find some link between the Force and straight edge. At the very least, they're two things people like a lot, so it makes sense to combine them, especially in the 90s. This vintage straight edge shirt from the late 90s, is a riff on the Star Wars logo.