VIETNAM

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Words: "Continued optimism cannot be justified. … I found that the kind of war we are fighting in Vietnam will not gain our long-range objectives, that the pattern of destruction we are creating can only make a workable political future more difficult."  --World Affairs Council of Boston, Jan. 25, 1968

Actions: In the late 1960s, Kennedy gradually came to oppose the war his brother John had begun, though he never became as vocal an opponent as his brother Bobby. In one of his first leadership positions, chair of the Senate Judiciary Subcommittee on Refugees and Escapees, Kennedy lobbied the Lyndon B. Johnson administration to take more care with civilian casualties and refugees, making a trip to Vietnam in 1965.

In 1968, he returned to the country, this time sending staffers ahead to identify problems and cut through military spin. Kennedy was shocked by the endemic corruption of the South Vietnamese government and what he saw as a disregard for civilian life by U.S. forces. He returned a vocal Vietnam opponent, bringing his concerns directly to the White House. In 1973, he sponsored a successful resolution against further spending on the war.

The Vietnam experience heavily influenced his thinking on military intervention. He would later refer to Northern Ireland as "Britain’s Vietnam" and Iraq as "George Bush’s Vietnam."

SOUTH AFRICA

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Words: "My nation will not long continue a policy of so-called constructive engagement with a social order so entirely destructive of human rights. Only a very few extremists in my country still defend the government of South Africa. Patience is running out across the [American] political spectrum. Not only Democrats, but Republicans and President Reagan even are speaking out against apartheid."  --Cape Town, South Africa, Jan. 12, 1985

Actions: Kennedy was an early and vocal U.S. advocate for South Africa's anti-apartheid movement. In 1985, at the invitation of Archbishop Desmond Tutu, Kennedy toured South Africa to meet with movement leaders including Winnie Mandela, wife of then-jailed dissident leader Nelson Mandela, and bring international media attention to their fight. Kennedy famously held an illegal rally outside Pollsmoor Prison where Mandela was being held, an event the South African president and Nobel Peace Prize winner later said "gave us a lot of strength and hope."

The next year, Kennedy sponsored the Comprehensive Anti-Apartheid Act, which put in place the first U.S. sanctions on the South African government, and pulled together enough votes to overturn Reagan's veto, a remarkable feat given the Republican Senate majority at the time. It was the first time a president's foreign-policy veto had been overturned in the 20th century.

CHILE

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Words: ''I am told that there are some people who regard me as an enemy of Chile. I am not an enemy of Chileans, I am an enemy of kidnapping, murder, and arbitrary arrests.'' -- Santiago, Chile, Jan. 16, 1986

Actions: Kennedy's strident opposition to the regime of Chilean strongman Augusto Pinochet began almost immediately after the Sept. 11, 1973, coup, when the senator helped negotiate the release of a number of political prisoners, including Defense Minister Orlando Letelier (who was later assassinated in Washington). He also sponsored the 1976 "Kennedy Amendment," which banned U.S. arms sales to Pinochet’s government.

In 1986, Kennedy paid a tense visit to Chile to meet with democracy leaders. Pinochet refused to meet with the senator, calling him an “enemy” of the country. The general’s supporters pelted Kennedy’s motorcade with eggs and held up pictures of Mary Jo Kopechne, the woman who was killed in a car accident with Kennedy in 1969 on Chappaquiddick Island, Mass.

Kennedy remained popular with the Chilean opposition and in 2008, current President Michelle Bachelet (above), who was imprisoned and tortured under the Pinochet regime, awarded him the country’s highest civilian honor -- the Order of Merit -- calling him "a friend to Chile in our hour of need."

NORTHERN IRELAND

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Words: "To nationalists who have suffered decades of injustice and discrimination, I say, 'Look how far you have come ... have faith in yourselves and in the future.’ And to Unionists who often feel afraid of what the future may bring, I recall that you are descendants of the pioneers who helped build America and now you can be the pioneers who build a better future for this island." -- Derry, Northern Ireland, Jan. 9, 1998.

Actions: Kennedy's most lasting contribution to international affairs may be his role in the Northern Ireland peace process. The Irish-American senator began as fierce advocate of Irish nationalism who made a point of showing it by wearing a green tie whenever British Prime Minister Margaret Thatcher was visiting Washington. But in later years he moderated his views, supporting negotiations between the two sides.

In 1994, Kennedy lobbied President Bill Clinton to grant a U.S. visa to Sinn Fein leader Gerry Adams so that he could attend a pivotal peace conference, over the objections of the British government. Just a few months later, the Irish Republican Army (IRA) declared a ceasefire. A decade later, Kennedy would snub Adams by canceling a meeting over continued violence perpetrated by the IRA.

Kennedy maintained his links with the leadership of Sinn Fein and continued to publicly criticize abuses by the British military, but was also willing to criticize the republican side over continued terrorist violence. He urged Irish-Americans not to financially support the IRA.  In 2007, Kennedy was present at the “miracle of Stormont,” (above) the creation of a coalition government with Sinn Fein leader Martin McGuinness and Protestant leader Ian Paisley. Both men praised Kennedy’s role in making the event possible, and the senator was awarded an honorary knighthood in 2009 for his contributions to the peace process.

IRAQ

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Words: "There is clearly a threat from Iraq, and there is clearly a danger, but the administration has not made a convincing case that we face such an imminent threat to our national security that a unilateral, pre-emptive American strike and an immediate war are necessary. Nor has the administration laid out the cost in blood and treasure of this operation. With all the talk of war, the administration has not explicitly acknowledged, let alone explained to the American people, the immense postwar commitment that will be required to create a stable Iraq.” —The Johns Hopkins University School of Advanced International Studies, Washington, Sept. 27, 2002

Actions: Kennedy was a consistent opponent of the war in Iraq, calling his 2003 vote against authorizing military force "the best vote I've cast in my 44 years in the United States Senate." He would continue to assail the administration’s conduct of the war, which he believed was “a war of choice” that was “cooked up in Texas” based on faulty intelligence. He consistently irritated the White House by comparing the war to Vietnam, and starting in 2005, he began calling for a withdrawal of U.S. troops.

Perhaps less presciently, Kennedy also opposed the 2007 Iraq troop “surge,” predicting it would merely compound the war’s flaws. He introduced legislation that would require congressional approval for further escalation. Unfortunately for Kennedy, few Democrats were ever willing to go as far as him in opposing the war. But his consistent stand on the issue helped cement a late-career reputation as a champion for liberal Democrats, and his ringing endorsement of Iraq War opponent Barack Obama during the Democratic primary was a key moment in the 2008 presidential campaign.