President Obama compared ISIS to Heath Ledger's Joker in 'The Dark Knight'
According to the story, in 2014 Obama worried that US intelligence was not taking seriously enough the threat of ISIS, also known as ISIL, which has grown rapidly and is notorious for videos of beheadings and its use of social media for propaganda and recruiting.
Here's how Obama reportedly explained to advisers the group's relationship to the larger forces at work in the Middle East and why it could be so harmful:
This does in fact explain what makes Heath Ledger's Joker so terrifying, not just for Ledger's unhinged performance, but within the story of "The Dark Knight": He's free even from the relative system of rules abided by fellow criminals. He's total chaos and unpredictability - which is indeed how many see the threat of ISIS and its techniques.
Here's the scene from "The Dark Knight" Obama was referring to: