Jimmy Kimmel joked on Monday that he’s finally found proof that Donald Trump is, in fact, a “bonehead.”

Trump recently told Fox News’ Brian Kilmeade that he’ll know when his war on Iran is over “when I feel it, when I feel it in my bones.”

“That’s a problem,” said Kimmel. “He uses his bones to feel things instead of his brain. He’s a bonehead through and through. And the answer is he doesn’t know when this war is going to be done. The only war Trump had an exit plan for was Vietnam.”

Watch Kimmel’s full monologue here: