President Barack Obama's policy debates are part of his larger struggle to build a lasting legacy. Obama has studied the extraordinary achievements of Abraham Lincoln and other widely revered presidents. But he can also learn from presidents who are forgotten because their mistakes or circumstances helped to bury their legacies.

Enduring presidential legacies require presidents to do things that will withstand the test of time. To build lasting legacies, presidents need successors to build on and invest in their visions, and they must forge critical alliances across party lines.

Consider, for example, James Monroe, the only man besides Obama to be the third president in a row to be re-elected. Once wildly popular, Monroe is now largely forgotten. His first term was known as the "era of good feelings" because there was no viable opposition party. When he was re-elected in 1820, he won every electoral vote but one.

After he had the executive mansion painted white to cover damage from fires the British set in 1817, it became popularly known as the White House. Most Americans don't know this. They remember little about his presidency except the "Monroe Doctrine" that supports American intervention to protect the Americas from European interference. The doctrine endures because subsequent presidents have adhered to it.

Monroe's record is largely forgotten. His legislative achievements eroded over time. He authorized two of the most significant laws enacted in the 19th century - the Missouri Compromise, which had restricted slavery in the Missouri territory, and the Tenure in Office Act, which restricted the president's ability to remove certain executive branch officials without Senate approval. Subsequent presidents differed over these laws' constitutionality and tried to repeal or amend them. Eventually, the Supreme Court struck them both down.

Monroe had no distinctive vision of the presidency or Constitution. He entered office as the last member of the Virginia dynasty of presidents. But he had nothing to offer that could match the vision and stature of the three other members - Washington, Jefferson and Madison. Even with no opposition party, he was unsure where to lead the country.

Grover Cleveland, another two-term president, is only remembered, if at all, as the only man to have served two nonconsecutive terms as president. Cleveland's actual record is forgotten. He devoted his entire first term to vetoing laws he thought favored special interests, ultimately casting more vetoes than any president besides FDR; and he rallied the American people to side with him when the Senate retaliated against his efforts to remove executive officials to create vacancies to fill by stalling hundreds of his nominations.

Cleveland's constant clashes with Congress took their toll. In his second term, his stubbornness prevented him from reaching any meaningful accord to deal with the worst economic downturn in between the first and second great depressions.

Calvin Coolidge had the vision and rhetoric required for an enduring legacy, but his results failed the test of time. He was virtually unknown when he became Republican Warren Harding's vice president. When Harding died, Coolidge inherited a scandal-ridden administration. He worked methodically with Congress to root out the corruption in the administration and easily won the 1924 presidential election. Over the next four years, he signed the most significant federal disaster relief bill until Hurricane Katrina and the first federal regulations of broadcasting and aviation. He helped to create the World Court and the Kellogg–Briand Pact, which outlawed war.

Coolidge's vision had wide appeal. His conviction that the business of America was business still resonates among many Republicans, and he could have easily won re-election in 1928. But he lost interest in politics after his son died shortly before the 1924 election. He did not help his Secretary of Commerce Herbert Hoover win the presidency in 1928 and silently watched as the economy lapsed into the Great Depression.

As Obama winds his way through the first year of his second term, he cannot stand above or apart from the fray like Monroe and Coolidge. He must lead the nation through it. He must work with Congress rather than battle it as Cleveland did.

On many issues, including gay rights and the debt ceiling, Obama's detachment has allowed him to be perceived as being led rather than leading. He still has a chance to lead through his words and his actions and define his legacy as something more than having been the first African-American president.

Unlike forgotten presidents, he still has the means to construct a legacy Americans will value and remember, but to avoid their fates he must use those means - now.

Michael Gerhardt is a professor of constitutional law at UNC-Chapel Hill, and the author of "The Forgotten Presidents: Their Untold Constitutional Legacy." He wrote this for The Free Lance-Star in Fredericksburg, Va. Email him at gerhardt@email.unc.edu.

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