President Obama -- Strikes Lightning Pose ... With Usain Bolt

President Obama just met with the most powerful man in Jamaica ... Usain Bolt ... who made such an impression on POTUS, the guy struck Bolt's famous lightning pose.

You gotta watch the clip, Obama is totally geekin' out over meeting the fastest man on the planet.

In fact, he gushed about Bolt to the room ... saying, "Nobody's ever been faster than this man ... EVER ... of all the billions of people."

Obama is supposedly in Jamaica on political business ... but it looks like it's all a cover to get to Usain.

MORE FIYAH!!!!!!