All five living U.S. presidents are attending the dedication of the George W. Bush Presidential Center at Southern Methodist University in Dallas, Texas. Here is a look at their political legacies.
Jimmy Carter, 39th U.S. President
Jimmy Carter served as a U.S. Naval officer, a Georgia state senator and the governor of Georgia before serving as U.S. president from 1977-1981. The Democrat created two new Cabinet-level departments during his presidency - The Department of Energy and the Department of Education.
Carter worked on the Camp David Accords, which became a bilateral peace agreement between Egypt and Israel. He is still vocal in working toward a peace agreement between Israelis and Palestinians.
His time in office was plagued by a U.S. energy shortage and the Iran hostage crisis. A group of Islamist students held 52 Americans hostage for 444 days after storming the U.S. embassy in Tehran in 1979.
George Herbert Walker Bush, 41st U.S. President
George H.W. Bush served as a U.S. congressman, the ambassador to the United Nations and the director of the Central Intelligence Agency before his term as U.S. president from 1989-1993.
The Republican was president when the Berlin Wall fell in 1989 and the Soviet Union dissolved two years later. He ordered military operations in Panama and the Persian Gulf and signed the Immigration Act of 1990, which increased legal immigration to the U.S. by 40 percent.
He oversaw the nation as an economic recession swept across the United States, ultimately losing favor with the public when he allowed Congress to increase taxes.
Bill Clinton, 42nd U.S. President
Bill Clinton served as the governor of Arkansas before serving as U.S. president from 1993-2001. He is married to former Secretary of State Hillary Clinton, who also is a former U.S. senator.
Clinton successfully pushed for welfare reform and signed the North American Free Trade Agreement into law, creating a trilateral trading bloc between the U.S., Canada and Mexico. The U.S. created a budget surplus during the last three years of the Clinton administration.
Clinton's desire for universal health care in America manifested in a failed health care reform package that would have mandated employers to provide health insurance coverage to all of their employees. His time as president was marred by a sex scandal involving a White House intern.
He and former President George Herbert Walker Bush teamed up to form the Clinton Bush Haiti Fund, which helped victims of the 2010 earthquake in Haiti.
George Walker Bush, 43rd U.S. President
George W. Bush, the eldest son of George H.W. Bush, was the governor of Texas before serving two terms as U.S. president from 2001-2009.
Eight months into his presidency, the Islamist terrorist group al-Qaida hijacked passenger airplanes to attack major U.S. buildings. Two planes hit the World Trade Center's twin towers, one hit the Pentagon and a fourth heading for Washington, D.C. crashed into a field in Pennsylvania after its passengers tried to overcome the hijackers. Nearly 3,000 people died in the attacks.
Bush declared a "War on Terror" after the attacks and ordered U.S. troops into Afghanistan to overthrow the Taliban regime and hunt down al-Qaida leader Osama bin Laden. International support for the War on Terror waned when Mr. Bush and several other nations invaded Iraq in 2003, which resulted in the fall of Iraqi dictator Saddam Hussein.
Bush enjoyed an approval rating of 90 percent, the highest of any president, following the September 11 attacks in 2001. His approval rating plummeted to 22 percent by the time he left office.
Barack Obama, 44th U.S. President
Barack Obama served as a U.S. Senator from Illinois before serving as president from 2009 until now. He is the United States' first African American and multiracial president.
Obama ordered the military operation in 2011 that killed Osama bin Laden, the leader of the al-Qaida terrorist network. He also ended U.S. combat operation in Iraq.
His term has been plagued by the worst economic recession in decades. His economic policy has used U.S. government stimulus money to try to grow the nation's sluggish economy, as the U.S. national debt has ballooned to more than $16.8 trillion.