I agree that's what GP wrote, but I think GP's point is that it's not illegal for journalists to have classified documents, so it does not qualify as probable cause.
It's amazing how many people offer free internet advice off of ideological groupthink rather than actual laws.
This raid was authorized by a warrant. Do you really think a judge doesn't know the law, but you do?
If a crime happens in your neighborhood, and you have a camera, the cops could get a warrant to search your footage. It doesn't mean you committed a crime, it just means you can be compelled to provide information pertaining to an investigation.
Especially, if as is the case here, the criminal was already behind bars.