John Ratcliffe: “The primary role of the Federal Government is to provide for the common defense, and the single-most important part of…”

It's permissible to use it to communicate and coordinate for work purposes.

Not that I'm aware of.

I didn't transfer any classified information, and at the end of the day, what is most important is that the mission was a remarkable success.

I think that's an offensive line of questioning. The answer is no!