WASHINGTON - No matter what President Barack Obama tries to accomplish in the next four years, one of his biggest challenges might be avoiding the kind of missteps that have tripped up many of his predecessors in their second terms.
Richard Nixon resigned amid the Watergate scandal. Ronald Reagan got entangled in the Iran-Contra debacle. Bill Clinton was impeached over a different kind of affair. George W. Bush became more deeply mired in the Iraq war and faced the worst economic crisis since the Great Depression.
The second-term curse has bedeviled presidents as far back as George Washington, who grew tired of battling a persnickety Congress, and Abraham Lincoln, who was assassinated just weeks into his second term.
"Most presidents who serve two terms have had some kind of profound crisis within the second term," said Peter Kastor, an American history professor at Washington University in St. Louis.
Only four two-term presidents -- James Monroe, Teddy Roosevelt, Calvin Coolidge and Dwight Eisenhower -- managed to finish their second term without some sort of calamity.
Political scientists say there are lots of reasons presidents run into such trouble. Often, their most experienced Cabinet secretaries and advisers depart for more financially lucrative opportunities, leaving them to rely on a second- or even third-string team. Second-term presidents often have little, if any, real political capital since they are barred from running for another term and are in effect lame ducks the minute they take the oath of office a second time.
Sometimes, presidents are forced to deal with crises caused by external events over which they have no control. Other times, the crises they encounter are disasters of their own making.
"Sometimes these are the result of the hubris that develops from too long a tenure in office," wrote political scientist John P. Burke in a report posted in November 2012 on the website for the Center for the Study of the Presidency and Congress.
Franklin D. Roosevelt tried to pack the Supreme Court with justices who favored his New Deal policies, a disastrous display of chutzpah considered one of the worst mistakes of his presidency. Andrew Jackson waged war against the national bank, a vendetta that helped thrust the nation into a deep depression.
Another explanation for second-term woes may be simple exhaustion -- on the part of both the president and the public, said Jeffrey Engel, director of the Center for Presidential History at Southern Methodist University in Dallas.
"The battles that are required to achieve victory in domestic politics in particular are simply tiring and unappealing after five, six, seven years," Engel said.
A year or two into a president's second term, the American public starts to lose interest in the current occupant of the White House as the focus shifts to who his successor will be.
"People grow tired of a person's act in the second term," Engel said.
To avoid the second-term curse, Obama needs to take charge and frame the political debate on the issues of the day, whether they are fairness in taxation, closing corporate tax loopholes or instituting gun control, said David Coates, a professor of Anglo-American studies at Wake Forest University.
"He can either try to be bipartisan and try to strike a deal with the Tea Party element in the House, where you get some short-term effective legislation, or you decide you are going to play the longer game," Coates said.
If Obama really wants to accomplish anything in the next four years, he should focus heavily on helping Democrats take back control of the House in 2014, Coates said. Without a new Congress, "I don't see how he can do very much in his second term," Coates said.
Engel suggests Obama look beyond America's shores over the next four years. While presidents may lack the political capital to carry out much of their domestic agenda in their final years in office, they often have better luck with foreign policy because they are seen as world statesmen and, at times, are better received abroad than at home.
"If you can create goodwill and become a more popular president, a more beloved president, because of accomplishments overseas, that will give you extra gravitas to get things done at home," Engel said.