Sean Penn has joined George Clooney, Judd Apatow, Aaron Sorkin and Barack Obama in blasting Sony for its decision to pull “The Interview” from release. In a letter sent to Mother Jones, Penn noted that Sony’s move — which happened after the company reportedly put the fate of “The Interview” in the hands of theater owners, who decided against running the film — had given ISIS “a commanding invitation.”

“I believe ISIS will accept the invitation,” Penn wrote. “Pandora’s box is officially open.”

As with Clooney and Apatow, Penn noted that Sony’s decision set a disturbing precedent:

The damage we do to ourselves typically outweighs the harm caused by outside threats or actions. Then by caving to the outside threat, we make our nightmares real. The decision to pull ‘The Interview’ is historic. It’s a case of putting short term interests ahead of the long term. If we don’t get the world on board to see that this is a game changer, if this hacking doesn’t frighten the Chinese and the Russians, we’re in for a very different world, a very different country, community, and a very different culture.

Late Friday, Sony released a statement defending itself against claims that it had made a misstep in its handling of “The Interview.”

Sony Pictures Entertainment is and always has been strongly committed to the First Amendment. For more than three weeks, despite brutal intrusions into our company and our employees’ personal lives, we maintained our focus on one goal: getting the film The Interview released. Free expression should never be suppressed by threats and extortion.

The decision not to move forward with the December 25 theatrical release of The Interview was made as a result of the majority of the nation’s theater owners choosing not to screen the film. This was their decision.

Let us be clear – the only decision that we have made with respect to release of the film was not to release it on Christmas Day in theaters, after the theater owners declined to show it. Without theaters, we could not release it in the theaters on Christmas Day. We had no choice.

After that decision, we immediately began actively surveying alternatives to enable us to release the movie on a different platform. It is still our hope that anyone who wants to see this movie will get the opportunity to do so.

Read Penn’s letter over at Mother Jones.