No one should be surprised that the presidential election has been so close. For weeks, opinion polls have told us it would be.Now that Election Day is done, there is no time to waste before resolving some urgent problems.President Barack Obama, headed for re-election according to late returns Tuesday night, must focus attention on the "lame-duck" session of Congress that begins next week and intensifies after Thanksgiving..The sluggish U.S. economy, showing some signs of life with higher-than-expected job growth last month, has been the overriding issue of the campaign and must receive immediate attention.The so-called "fiscal cliff," the combination of tax increases and federal spending cuts scheduled to go into effect after the end of the year, could send the economy spiraling downward again, the nonpartisan Congressional Budget Office has said. There are ways to avoid that, but they require both presidential and congressional leadershipIn fact, they require the kind of compromise we have not seen while the election season has kept both Republicans and Democrats in hardened ideological bunkers.The "cliff" could mean the loss of more than $600 billion from the economy, the CBO says. Ironically, it's the result of a grotesque 2011 congressional compromise, a "stop me before I kill again" way to cut the federal deficit if leaders couldn't cut the federal deficit any other way.It includes ending the temporary payroll tax cut enacted last year, a direct hit to consumer pocketbooks. Also on the list is withdrawal of the Bush-era tax cuts.The CBO says the removal of tax cuts would mean an economic hit of $399 billion. Spending cuts would amount to $102 billion, and other measures $106 billion.The deficit is a serious economic problem on its own. but the fiscal cliff is a suicide jump.The cliff is a creature of Congress. There is no magic to the Dec. 31 deadline. Congress could prolong action until next year. Still, the uncertainty of inaction hurts the economy, too.There are plenty of other issues that need attention: foreign policy, immigration, Social Security, Medicare, education, energy. But the most pressing problem is the economy.Presidential leadership will be put to the test right away.