Why do newspapers leak military secrets that could benefit their country?

I was watching a documentary on the CIA operation to take a russian sub. The mission ended when a LA times article exposed the entire operation, forcing the government to give up.

I understand leaking government secrets if its unethical and violates human rights, but in cases like this, it is clearly for the benefit of the US and was not going to harm the rights of any US or Russian citizens.

Why would newspapers leak such missions jeopardizing the country?