WASHINGTON — The pressure's on for Barack Obama, orator.

History wants something for the ages in his Jan. 20 inaugural speech. Not just pretty words that melt like gumdrops but something that will settle in the nation's soul and be worth making schoolchildren memorize 100 years from now.

Americans want something for the dispiriting times they live in. They have their first extraordinary speaker in decades taking the oath of office. They know how good he's been. Time for great.

How tall is the order? "The great task of Barack Obama is to be a John F. Kennedy or to be a Ronald Reagan — truly inspire the American people and in a few succinct, memorable lines, lay out for the country your new vision for America," says American University political historian Allan J. Lichtman.

Gulp.

At least that does not call upon Obama to be another Abraham Lincoln, the unsurpassed cosmic communicator whose words and deeds the president-elect often cites, and probably will again from the stage of the Capitol.

Obama can be expected to hit upon all lodestar themes from the canon of inaugural speeches. Some of them are unity, hope, change, continuity, security and God. (Prosperity, another biggie, may have to wait.)

The historic ascension of a black man to the White House begs for eloquent acknowledgment. Students of inaugural speeches expect that in brief. Just seeing Obama take the oath may say more on that subject than his rhetoric could.

One of the memorable characteristics of inaugural addresses is how forgettable most of them are.

Perhaps not since Reagan declared "government is not the solution to our problem, government IS the problem," has a line with staying power come from an inaugural speech. Even that thought was only satisfying to the ideologically like-minded. But it showed the change Reagan wanted for his country.

"The number of really plodding speeches is almost countless," says Leo Ribuffo, history professor at George Washington University. "The ones that stand out: maybe eight-nine if you're a historian, maybe three or four if we just have a vague sense of the past."

Count Lincoln, Franklin Roosevelt, Kennedy, Thomas Jefferson and one or two more as the acknowledged masters.

Jefferson's first inauguration, in 1801, was the first that marked the transition between rival parties.

"We are all Republicans, we are all Federalists," he said, reaching to erase bitterness between parties of the day.