For more on the national security implications, we turn now to Leon Panetta.

He served as Secretary of Defense and director of the CIA during the Obama administration, among many other roles in government.

Welcome back to the news hour, sir.

How does this lapse strike you from an operational security perspective, that the country's top national security officials shared

information about an imminent strike, an imminent attack on a commercial messaging app?

Well, look, this is a serious security breach, particularly when it comes to war plans. Look, war plans, attack plans

are among the most sensitive and classified information that you can have. And it has to be

handled with care. I think it was a mistake to have a conversation on a Signal app that is not approved for

sharing classified information.

So I'm not sure why they even placed any of this information on Signal. But nevertheless, the fact that it included somebody

who was not cleared for that information, and as a matter of fact, was a member of the press,

is a serious breach and one that needs to be fully investigated. What are the traditional secure channels for this type of discussion?

How would this normally unfold?

Well, when I was both director of the CIA and Secretary of Defense,

when it came to attack plants, the discussion was reserved for the

situation room in the National Security Council, which is highly protected and is a place

where you can have that kind of discussion without having to worry whether or not any of that information would leak.

So I'm a little bit taken aback that they would have this kind of conversation on a commercial messaging network. That just strikes me

as being pretty careless. How might a foreign intelligence service, a foreign country trying

to do the U.S. harm, how might they use this kind of information, or how might they exploit,

what appear to be lax security

practices?

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