Rep. Jim Cooper weighs in on Trump document search

U.S. Rep. Jim Cooper has spent the last two decades in Congress navigating the government's "hardcore" rules for handling classified documents related to the nation's security.

• "The careless handling of information is negligent and reckless," Cooper tells Axios while reflecting on news that the FBI seized classified and top-secret documents from former President Trump's Florida home.

Driving the news: Earlier this month, the FBI executed a search warrant at Mar-a-Lago.

• In a court filing, the Department of Justice chronicled 11 sets of classified materials confiscated from Trump's home.

Why it matters: Cooper (D-Nashville) called the handling of classified materials "one of the central roles of government" because "we know there's hacking going on." The nation's security depends on handling sensitive documents correctly, he says.

• "The efforts of spies to take these secrets is legendary," Cooper says.

Zoom in: As a longstanding member of the House Intelligence Committee and current chairman of the subcommittee on strategic forces, which oversees the country's nuclear arsenal and space programs, Cooper regularly handles such secret documents.

The intrigue: Cooper described to Axios how the intelligence committee meets in a lead-lined vault, how members are barred from bringing in cell phones and how documents are specially numbered to track who handles them.

• "Some people have argued that nothing should be classified, but the classification system is very hardcore and hierarchical."

What he's saying: "I've been around a long time, and I know a lot of history," Cooper tells Axios. He pointed to the case of Sandy Berger, a former national security adviser who was fined for inappropriately handling documents that he used to prepare for testimony in front of the congressional 9/11 commission.

• "Forget politics, I don't care which former president tried to do this. It's outrageous and should be punished. I hope people, whether Trump supporters or not, can understand it only weakens America if these secrets are allowed to be stolen. If you carelessly handle them or invite their theft, that is a terrible breach of your responsibility to the nation."

The other side: Trump has said he verbally declassified the documents, arguing that they weren't mishandled. He's called the Department of Justice investigation politically motivated.