When she confirmed that Trump's temper would get us all blown to smithereens.
He's insulted public officials and world leaders without consequence, demeaned women and has even barred journalists for writing about him in a negative light, even when their zingers are truthful. We've already seen his hot-headedness almost stale our ties with our allies, and Obama knows having him as the commander-in-chief would only spell more disaster.
Barack Obama is the epitome of level-headed and cool, which is exactly the temperament the first lady said is needed do the job well.
"When you have the nuclear codes at your fingertips and the military in your command, you can't make snap decisions," she said. "You can't have a thin skin or a tendency to lash out. You need to be steady and measured and well-informed."
When she subtly told racists to have a fucking seat.
From the moment she took office, Obama hasn't been shy about calling out bigotry and speaking out against scapegoating ethnic groups. She's championed Black women, and reinforced the message that Black lives do matter.
She's also real about American history, which is primarily full of the enslavement of her ancestors. That's not lost on her. Breaking barriers is what she and Clinton are all about.
Obama said that Clinton breaking the glass ceiling to be the first nominee for a major party is "the story of this country."
It's the story that has brought me to this stage tonight, the story of generations of people who felt the lash of bondage, the shame of servitude, the sting of segregation, but who kept on striving and hoping and doing what needed to be done so that today I wake up every morning in a house that was built by slaves.""And I watch my daughters, two beautiful, intelligent, black young women playing with their dogs on the White House lawn. And because of Hillary Clinton, my daughters and all our sons and daughters now take for granted that a woman can be president of the United States."
Last but not least, when she told Trump that America doesn't need to be made great again. We're doing just fucking fine, thank you.
"So, look, so don’t let anyone ever tell you that this country isn’t great, that somehow we need to make it great again," she said. "Because this right now is the greatest country on earth!"