In the 1980's the International Whaling Commission (IWC) put a "moratorium" on the killing of all species of whales for profit or also known as whaling. However, Sperm whales are still being murdered to this day. The US, Japan, Norway, Denmark, Iceland, Russia, and some smaller Carribean countries still are engaged in whaling.  Denmark and Russia hunt and kill whales due to tradition however, places like Japan, Norway and the US kill Sperm whales for "research purposes”. Sperm Whales are important to maintaining the stability of the oceans food chains by being an apex predator. If we allow some exceptions to the whaling rule, the exceptions will get wider and wider until we eventually bring back whaling and the extinction of Sperm Whales occur, and then their ocean habitats goes into a state of instability. If we instead close off all Sperm whale killings, we preserve the entire Sperm whale population.