Biden's farewell speech warning that oligarchs pose a threat to democracy has echoed a growing problem in the world, economic and historical experts say.

President Joe Biden participates in a bill signing ... a political scientist and lecturer in statistics at the University of Michigan's Gerald R. Ford School of Public Policy, told ABC News.

Kenneth W. Mack is the inaugural Lawrence D. Biele Professor of Law and Affiliate Professor of History at Harvard University. Joe Biden faced a set of nearly unique challenges as president.

"I think it is likely Joe Biden's legacy will be assessed far more generously than some would have it today," said Ellen Fitzpatrick, professor of history at the University of New Hampshire.

With some two weeks left at the helm, President Joe ... Biden said there has been a push to see him link his library with the Biden School of Public Policy and Administration at the University ...