When NBC sent out its weekly Tonight Show listings yesterday, there was a curious lack of guests for November 19. Ben Harper and Charlie Musselwhite have the music gig, but there wasn’t a headliner. Now we know why. The network spilled to the AP today that President George W. Bush will make his fourth appearance on the Jay Leno-hosted show that night, taking about life after the White House. It’s a solid get for the show, as the former commander-in-chief has kept relatively quiet since leaving office in 2009, rarely giving extended interviews. He most recently sat with Leno in November 2010. Not a bad November sweep for The Tonight Show thus far, politically speaking: Tea Party champion Sen. Ted Cruz made his debut on the late-night circuit with Leno this past Friday.