Tonight is a bookend for Hopenchange twice over. It’s a bookend to Trump’s rise politically during the Age of Obama, at least if you believe the armchair psychologists who say O’s 2011 White House Correspondents Dinner speech goofing on Trump lit a fire under him to earn the respect of the political class. Obama was the one who unwittingly baited Trump into running for president; now he has to help drag Hillary over the finish line to prevent him from winning. In a larger sense, this is a bookend to Obama’s entire career as a national figure, which began in earnest with his speech at the 2004 Democratic national convention. That was his first attempt to define who Americans really are — not red states or blue states, he insisted, but United States. Twelve years later whatever unity there was at the time is all but gone, yet count on O to return to his favorite theme tonight and try to scold Americans into dumping Trump. He’s on the wrong side of history, his politics is “not who we are” — you’ve heard this song a thousand times and all it’s done so far is produce a Trump/Clinton election. But Obama will never give up on his heartfelt belief that if he can just explain to people how backward they’re being, they’ll come around. Perfect approach during a populist political climate, don’t you agree?

Actually, given free rein, I think Obama would prefer to vent his contempt for Trump at length rather than doing his “better angels of our nature” shtick, but that would probably backfire in being seen as unpresidential. O is an asset for Clinton right now because of his rising job approval and Hillary has a thousand other Democrats willing and able to attack Trump on her behalf. What she needs from Obama is help persuading the Bernie fans and minority voters who turned out for O but might not turn out for her to go to the polls this fall. Expect a heavy emphasis tonight from him that Hopenchange will all have been for naught if Clinton isn’t elected to protect his legacy. If anyone’s going to knife Trump tonight, especially over his game of footsie with Putin, it’ll be Biden. He’ll speak directly before O during the 10 p.m. hour. It’ll be a good cop/bad cop routine with Officer Joe punching Trump repeatedly before Sergeant Barack strolls in and tells everyone with a straight face that American greatness can only be achieved by electing Hillary Clinton, of all people, as president. To repeat my weeklong prediction: No convention bounce for Herself. We’ll see. Here’s your Twitter widget for real-time commentary from the Hot Air crew.