Joe Biden formally introduced Sen. Kamala Harris as his running mate on Wednesday, telling a socially-distanced gymnasium in Wilmington, Del.: "I have no doubt that I picked the right person to join me as the next vice president of the United States of America."

Why it matters: Harris is a historic pick for vice president, becoming the first Black woman and first South Asian woman to be named to a major-party U.S. presidential ticket. "Kamala knows how to govern," Biden said. "She knows how to make the hard calls. She is ready to do this job on day one."

What he's saying:

• "As a child of immigrants, she knows personally how immigrant families enrich our country, as well as the challenges of what it means to grow up Black and Indian-American in the United States of America. Her story is America's story — different from mine in many particulars, but not so different in the essentials."
• "This morning, all across the nation, little girls woke up — especially little Black and brown girls, who so often feel overlooked and undervalued in their communities. But today — today, just maybe, they are seeing themselves for the first time in a new way, as the stuff of presidents and vice presidents."
• "Donald Trump has already started his attacks, calling Kamala "nasty." Whining about how she is "mean" to her appointees. It is no surprise, because whining is what Donald Trump does best, better than any American president in history. Is anyone surprised Donald Trump has a problem with a strong woman or strong women across the board?"

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