Bring a large pot of water to a boil. Add salt and spaghetti, and cook according to package instructions; drain; return to pot.
Meanwhile, heat oil in a large skillet over medium heat. Add garlic, crushed red pepper, and anchovies, mashing them with a wooden spoon. Cook, stirring, until garlic is fragrant, 2 minutes.
Add tomatoes and juice, breaking up the tomatoes with hands, Stir in capers and olives. Bring to a boil; reduce heat. Simmer until thickened, 5 to 10 minutes. Toss with pasta; season with salt and pepper.