Editor's Note: Julian E. Zelizer is a professor of history and public affairs at Princeton University's Woodrow Wilson School. He is the co-editor of "Rightward Bound: Making America Conservative in the 1970s" and is completing a book on the history of national-security politics since World War II, to be published by Basic Books.
Historian Julian Zelizer says Obama should use Joe Biden to advance his agenda in Congress.
PRINCETON, New Jersey (CNN) -- Now that he is president-elect, Barack Obama must start thinking about what to do with Joe Biden.
Vice presidents have had very different roles in recent decades, particularly as the power of the office increased.
During the past eight years, we have watched Dick Cheney expand the influence of the vice president into virtually the policymaker-in-chief with his unprecedented role in shaping the war on terrorism.
Obama will face a number of herculean challenges starting in January. One of them will be to effectively work with a Democratic Congress where there remain major tensions with the executive branch, as a result of President Bush's aggressive use of presidential power, and growing divisions among different factions of the Democratic Party.
With the responsibility of controlling united government in difficult economic times, conflicts are likely to flare among Democrats as legislators realize that failure could result in a backlash.
This is where Joe Biden should come into the picture. Along with Rahm Emanuel -- who will be Obama's chief of staff -- Biden should be used by Obama as a point man on Capitol Hill to help twist arms, make arguments and build voting coalitions.
Biden has often said that his role model for the vice presidency is Lyndon Johnson, who served with John Kennedy from 1961 to 1963 before becoming president.
Biden has explained that "People knew -- as they know about me now -- that he understood politics in the broad terms of Congress, and he understood the detail of the legislation."
Biden has the right idea about what he could contribute as a long-term senator in the office of the vice president -- but has it wrong in terms of how he sees the history. Ironically, Lyndon Johnson should be a model for how the new administration should not treat the vice presidency.
Johnson was miserable during his time in the office and Kennedy did not use him well. LBJ could have been an enormous asset. He was a southerner and former Senate majority leader who could have helped Kennedy sell programs such as civil rights and Medicare in a Congress dominated by Southern conservative Democrats.
But instead of using Johnson as a legislative deal-maker, he isolated him from the political arena. Tensions between Johnson and Senate Democrats were partially to blame. Johnson's ego got in the way when he tried to keep his office in the Senate and suggested to Democrats that he should be invited to head their strategic meetings. His colleagues rejected the suggestion.
At the Democratic Conference meeting on January 3, 1961, Johnson was devastated when he heard colleagues who helped him gain power say they didn't want him there. Sen. Al Gore Sr. said, "This caucus is not open to former majorities."
Kennedy was also leery of Johnson's ambitions and circumscribed his interaction with Congress. Johnson's biggest roles were to help promote the national space program and to lead the White House Committee on Equal Employment, from which he pushed for civil rights initiatives.
Kennedy also sent Johnson on numerous overseas trips. According to his biographer Robert Dallek, "Kennedy was happy to have Johnson gather intelligence on what senators and representatives were thinking, but he had no intention of allowing him to become the point man or administration leader on major bills." Johnson bitterly remarked that the president was making no use of him in dealing with the Hill: "You know, they never once asked me about that!"
In the end, Kennedy did not have much success with legislation. Most of his major proposals languished in the congressional committee system and he was forced to use executive power to develop programs like the Peace Corps. The decision to constrain and isolate Johnson was clearly a mistake and didn't help his cause.
Johnson is also a negative example in terms of how, after becoming president when JFK was assassinated and then winning a race for the presidency in his own right, he treated his own vice president, Hubert Humphrey. From the start, Johnson understood that Humphrey could be an enormous source of strength with legislative relations.
The Minnesota senator had served as Johnson's chief liaison to northern liberals in the 1950s. He had proven enormously effective as Senate Whip at obtaining the votes needed for passage of the Civil Rights Act in 1964.
But from the start of his vice presidency, the relationship was full of tension. One month after the election, LBJ said that Humphrey was constantly trying to appear in the press and, after letting him see a memorandum about rumors that Johnson was dying from liver disease, he said "You'd like that, wouldn't you Hubert...."
Initially, Johnson did use Humphrey to help him sell the War on Poverty. According to the Senate Historical Office, Humphrey, known by many as the "field marshal on Capitol Hill," regularly "delivered votes from lawmakers who seemed immune to blandishments from any other quarter." Humphrey chaired a number of key committees on civil rights.
But, like Kennedy, Johnson eventually excluded Humphrey and limited his role. The problem came when Humphrey expressed strong doubts about America's escalating role in Vietnam. In 1965, Humphrey privately told the president that if they ended up "embroiled deeper in fighting in Vietnam over the next few months, political opposition will steadily mount."
Johnson's response was brutal. He did not allow Humphrey to participate in deliberations over the war and stripped the vice president of many duties. According to one aide, "He was frozen out, really sent to purgatory for a full year."
Johnson eventually brought Humphrey back into the inner circles of decision-making in 1966, but only after Humphrey changed his tune and agreed to sell the war in Vietnam in Congress. The decision would undermine his chances for the presidency in 1968.
Obama should think about Lyndon Johnson as a perfect example when he decides what to do with Biden -- but not in the way that Biden has suggested. Obama needs to use Biden to strengthen the chances for the administration's programs as they make their way through the House and Senate during extraordinarily difficult times.
If Obama takes Biden's words to heart and replicates Johnson's experience, he will lose one of his best weapons.
The opinions expressed in this commentary are solely those of Julian Zelizer.