President Joe Biden and President Andrés Manuel López Obrador of Mexico shake hands during a welcome ceremony at the 2023 North American Leaders' Summit.
The Chinese national flag flies behind security cameras on Tiananmen Square on June 4, 2012 on the 23rd anniversary of China's crackdown of democracy protests in Beijing.
Lawrence Summers, then Director of President Barack Obama's National Economic Council, participates in a question-and-answer session during a luncheon with the Economic Club of Washington at the J.W. Marriott April 9, 2009 in Washington, DC.
