Let's see: a guy in a Muslim tunic, who after being arrested tells police he has pledged allegiance to ISIS, and who has made trips to the Middle East, shoots 11 times at a Philly policeman, wounding him. What could be the shooter's motive? If you're Rachel Maddow, the answer is "murky" and "unclear." So said Maddow on her MSNBC show last night. View the video here.