Bring a pot to a boil for pasta, making sure to salt the water. In a large frying pan, add olive oil to coat the pan. Add garlic, shallots, parsley stems, and red pepper. Cook until garlic is fragrant and shallots begin to be translucent. Add in tomatoes and Calabrian chilies. On medium heat, add clams, clam juice, and dry white wine. Cover the pan to steam the clams and give them a couple of shakes throughout 5-10 minutes of steaming. Discard any clams that do not open. Remove parsley stems and take out the cooked clams, setting them aside. Add in cooked spaghetti, a ladle of pasta water, and chopped parsley. Toss until your preferred consistency is achieved. Serve and enjoy.