Ted: Oh, like Barney's theory about world peace?
[flashback to Barney talking to Ted at MacLaren's:]
Barney: So I explained to her. I said, Madeline, every single international conflict essentially boils down to sexual tension.
Ted: Every international conflict?
Barney: Every single one, dude.
Ted: So the crisis in the Middle East could be solved by...
Barney: Gaza Strippers. Next.
Ted: Apartheid?
Barney: Apart thighs. What else you got?
Ted: Cold War?
Barney: "Mrs. Gorbachev, take down those pants."