As Kamala Harris spoke on the last night of the Democratic National Convention, Donald Trump took to Truth Social to ask, “IS SHE TALKING ABOUT ME?” Even for a man notorious for deranged tweets, this was an all-timer. Trump is easily triggered, easily sent into angry spirals, easily knocked off-kilter by a light press of his emotional buttons, but Harris seems to push him into the fully unhinged.

That particular social media spree is hardly the only example of the former president melting down over his new opponent. Trump has questioned whether Harris is really Black. He has mocked her laugh. He appears particularly upset by the idea that the crowds gathering to see her are larger than his, so he suggested that she was using A.I. to fake the number of her fans. (She wasn’t.) As she delivered her remarks at the DNC, he posted, “WHERE’S HUNTER?” He tried to go after her running mate, Tim Walz, insisting: “Walz was an ASSISTANT Coach, not a COACH.” As Harris’ speech went on and Trump unraveled further, he did what he often does when he wants to vent: He called in to Fox News. During the 10-minute phone interview, he ranted and rambled and seemed to be accidentally pressing various buttons on his phone, punctuating the broadcast with random beeping—that is, until he was ultimately cut off.

When it comes to Harris, the man once known as “Teflon Don” is suddenly struggling to make his insults and accusations stick. Trump has long channeled his bad feelings into ridiculing and demeaning anyone who challenges him, often with derisive nicknames; his target list has included plenty of Republicans too. But some people appear to get under his skin more than others. One politician he seems to truly despise is Barack Obama, whom Trump targeted with the ugly and false “birther” claim that Obama was born not in the United States but rather in Kenya, the homeland of his father. Even after those claims were disproved again and again, Trump persisted. When Obama turned the tables and made fun of Trump and his birther conspiracies at the 2011 White House Correspondents’ Dinner, Trump was visibly steamed. Many in politics and media believe that that moment—that particular humiliation—is why Trump ran for president in 2016.

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