[264]

Subsequent activities (2017–2019)
Biden with Barack Obama and Donald Trump, at the latter's inauguration on January 20, 2017
After leaving the vice presidency, Biden became an honorary professor at the University of Pennsylvania, developing the Penn Biden Center for Diplomacy and Global Engagement. Biden remained in that position into 2019, before running for president.[265][266]
In 2017, Biden wrote a memoir, Promise Me, Dad, and went on a book tour.[267] By 2019, he and his wife reported that they had earned over $15 million since the end of his vice presidency from speaking engagements and book sales.[268]
Biden remained in the public eye, endorsing candidates while continuing to comment on politics, climate change, and the presidency of Donald Trump.[269][270][271] He also continued to speak out in favor of LGBT rights, continuing advocacy on an issue he had become more closely associated with during his vice presidency.[272][273] In 2018, he gave a eulogy for Senator John McCain, praising McCain's embrace of American ideals and bipartisan friendships.[274] Biden continued to support efforts to find treatments for cancer.