The populist presidential campaigns of Bernie Sanders and Donald Trump have been fueled by the deep disillusionment millions of Americans feel about what they believe is a rigged political and economic system. A stark rift has opened between those two candidates and the establishment wings of the two parties.
A similar rift has opened over foreign policy, and the issue separating the populists from the establishment candidates is the Iraq war.
In October 2002, Sen. Hillary Clinton voted for the resolution to authorize the use of force against Iraq. Bernie Sanders, then a congressman, voted against the use of force. In a speech on the House floor, he warned that the invasion of Iraq could destabilize the Middle East for years.
On Feb. 14, on CBS' Face the Nation, Trump said, "The war in Iraq has been a disaster. It started the chain of events that leads now to the migration, maybe the destruction of Europe. [George W. Bush] started the war in Iraq. Am I supposed to be a big fan?"
This is not the first time that disagreements over a disastrous foreign war have divided the Democratic and Republican parties.
Fifty years ago, the Vietnam War split the American political establishment, dividing the American people as no issue had since the Civil War. The war destroyed Lyndon Johnson's presidency and undermined support for the Democratic party. Richard Nixon won the 1968 election with a "secret plan" to end the war. It turned out that Nixon's plan was to try to win the war, which failed spectacularly.
For a generation, the so-called Vietnam syndrome kept the United States from undertaking any large-scale foreign military operations. The mere suggestion that a conflict could become "another Vietnam" was enough to galvanize public opinion against the dispatch of U.S. troops to some far corner of the world.
It wasn't until the end of the 1991 Gulf War that President George H.W. Bush could say, "By God, we've kicked the Vietnam syndrome once and for all!"
Today, 25 years later, U.S. public opinion has turned against the Iraq war, which is widely viewed as a "big, fat mistake," as Trump put it during the Feb. 13 Republican debate in North Carolina. Trump's criticism of the Iraq war puts him at odds with the other Republican candidates, as well as the establishment wing of the party.
The split is just as pronounced in the Democratic race.
It is likely that Clinton's 2002 vote on Iraq was the reason she lost the 2008 nomination to Barack Obama, who had spoken out early against the war when he was a state senator in Illinois. In her 2014 autobiography, Hard Choices, Clinton wrote: "I wasn't alone in getting it wrong. But I still got it wrong. Plain and simple."
A Washington Post-ABC News poll last May found that three-quarters of Democrats polled and more than half of the Republicans believed the Iraq war was not worth fighting.
In 2011, Robert Gates, who served as secretary of defense under both George W. Bush and Obama, told a group of West Point cadets, "In my opinion, any future defense secretary who advises the president to again send a big American land army into Asia or into the Middle East or Africa should have his head examined."
The bitter U.S. experience in Iraq has become a foreign policy litmus test, as the Vietnam War was two generations ago. The conflicts in Syria, Afghanistan, and Libya all look enough like the conflict in Iraq to cause deep anxiety on the part of the American public. An "Iraq syndrome" will make new military interventions a hard sell for any future Democratic or Republican president.
Sanders has echoed Obama's warnings about deeper U.S. involvement in Syria. During the Oct. 13 Democratic debate in Las Vegas, Sanders said, "I will do everything that I can to make sure that the U.S. does not get involved in another quagmire like we did in Iraq."
In spite of Clinton's mea culpas, she is tied to ongoing wars in Iraq, Syria, and Libya. She has positioned herself well to the right of Obama by calling for a no-fly zone in Syria, which would risk a direct military confrontation with Russia. Her call for a "more robust" U.S. military policy in the Middle East puts her seriously at odds with public opinion and once again could derail her quest for the presidency.
It was no surprise when Sanders challenged Clinton's support for the Iraq war. But if Trump wins the Republican nomination, he could opportunistically position himself as the anti-war candidate. Having to defend the political and economic status quo, as well as America's endless wars in the Middle East, would not be a winning hand for Clinton.
William Goodfellow is the executive director of the Center for International Policy in Washington. firstname.lastname@example.org