President Obama, on arriving in Israel today, joshed Israeli Prime Minister Benjamin Netanyahu about his enthusiasm for "red lines."

Here's the backstory: Netanyahu has publicly urged the international community, and especially the U.S., to set clear "red lines" for Iran's nuclear development, beyond which military action would be taken against the Iranian program. In Netanyahu's telling, which included a dramatic United Nations speech in which he held up a drawing of a literal red line, the world's failure to publicly set an appropriate limit for the Iranian nuclear program puts his country in real danger.

Here's what happens in the video: Obama, after walking off Air Force One and working a nearby rope line, is escorted by some Israeli officials, including Netanyahu, down the tarmac. One of the officials urges Obama to "follow the red lines," referring to a long stretch of red carpet. Both Obama and Netanyahu, who appear to be working very hard to project the friendliest and most jovial image possible, start laughing.

Obama quips, "Bibi is always talking about red lines. This is all a psychological ploy." Netanyahu, without missing a beat, says, "This was minutely planned." They both laugh.

It's a lighthearted moment, but one imagines that their behind-closed-door discussions about red lines are likely to be a little less jovial.

(Hat tip to BuzzFeed's Andrew Kaczynski for the video link.)