Justin's "cute little" routine isn't really meant to be scary. Potts is at a conference, the question about Doctor Banner is basic but morbid, and JARVIS' fate is entirely in Tony's hands. Short of completely destroying every Stark home the world over, Justin wouldn't know how to get rid of him, exactly; and even if he did, Tony could probably bring him back online. Or maybe he'd have to start over from scratch, and wouldn't that be a kick in the pants?

"I'm sorry, are you calling me a liar?"

Justin's lied before. He most definitely has, as Tony well knows. He didn't know what he was talking about his ass, but he hadn't backed down when faced with Iron Man and he certainly wasn't going to back down with faced with Tony Stark, Dick Extraordinaire, Rubber Of Failures In The Faces Of Others.

"Or have you lost your marbles? Yes, the American government. While what happened at the Stark Expo wasn't exactly something they appreciated, they still want those suits. You remember Senator Stern, don't you? The one who said 'fuck you' on national news television? Yeah, he really wants those suits. He wants them so much he helped me break Ivan Vanko out of prison several years ago. And you know what? Even after all that? They still want these suits. So, you know: surprise, it wasn't just me. The government you've been letting control that suit your friend the lieutenant colonel took? Pretty corrupt.

"Are you going to play twenty questions or are we going to get down to business? Let's be professional about this, how's that?"