Mark Zuckerberg: Out for a Run ... Looking Like POTUS

Mark Zuckerberg went for a casual jog Wednesday afternoon in Berlin ... with at least 5 dudes in stride to watch his back, front, and sides at all times.

The Facebook billionaire -- who pledged to run 365 miles in 2016 -- was recently the target of threats from ISIS, so you can understand the large entourage. Despite the tight coverage, Zuck's guys are not actual bodyguards, just FB execs traveling with him.