Donald Trump fired back at Hillary Clinton a day after she accused the Republican nominee of being too thin-skinned to have control of the country’s nuclear arsenal, ABC News reports.

Said Trump: “I think I have a great temperament, I have a temperament where I know how to win. She doesn’t know how to win, she’s not a winner. She doesn’t know how to win. And this country, if they choose her, this country will not be in good shape.”

He added: “I’ve had a beautiful, I’ve had a flawless campaign. You’ll be writing books about this campaign.”