John Oliver tore strips off Donald Trump's foreign and nuclear weapons policies on Sunday.
Last week, the GOP frontrunner revealed he'd be happy if more U.S.-friendly countries obtained nuclear weapons. In response, The "Last Week Tonight" host said Trump just wasn't informed enough when it came to discussing such serious and often highly delicate matters.
Oliver played a clip from the billionaire businessman's CNN town hall with Anderson Cooper in which Trump said we'd all be "better off if Japan protects itself against this maniac in North Korea."
Adding it'd be preferable if South Korea could also defend itself, Trump said he'd be happy for Saudi Arabia to have nuclear weapons.
"He says that with the confidence of a man who could easily find Saudi Arabia on a map if he was given three tries — and the map only included countries ending with 'Arabia,'" Oliver said.
Oliver then played President Barack Obama's views of Trump's comments.
"[He] doesn't know much about foreign policy, or nuclear policy, or the Korean Peninsula, or the world generally," Obama said.
"President Obama is basically implying there that you could fill a book with the things Donald Trump doesn't know," said Oliver. "That book being... the encyclopedia."
Check it out in the clip above.