Displaying orcas in captivity is good science and great for conservation education -- so say SeaWorld and most of the other facilities displaying cetaceans (whales, dolphins and porpoises) around the world. However, there are many who would disagree: researchers who study orcas in the wild, animal welfare advocates... even the founding father of SeaWorld!
In the words of George Millay, the man who opened the entertainment facility that has fallen under hot scrutiny in the Blackfish documentary, "SeaWorld was created strictly as entertainment. We didn't try to wear this false façade of educational significance."
The first SeaWorld park opened in 1964 in San Diego, California (where there is now a proposed bill that, if passed, will make orca shows illegal). They put their first orca on display one year later, only the fourth orca ever captured from the wild and the original 'Shamu'.
It wasn't until fifteen years after that education was introduced to the SeaWorld parks for the first time. A 1989 amendment to the Marine Mammal Protection Act in the USA meant that they had no choice but to bring in a supplement to their animal circus shows. However, a second amendment in 1994 meant that this entertainment industry could largely self-regulate and this is still the case today.