By Peter RoffConservative Commentator/Former Senior Political Writer, United Press International

"Patton," the 1970 Academy Award-winning biopic about the legendary World War II commander, concludes with a wide shot of the general, now dismissed from his command of Third Army in disgrace, taking a lonely walk across an open field accompanied only by his dog Willie.

Over that image we hear the voice of actor George C. Scott, (who went on to win but turned down the Best Actor Oscar for his portrayal of Patton) saying:

"For over a thousand years, Roman conquerors returning from the wars enjoyed the honor of a triumph -- a tumultuous parade. In the procession came trumpeters and musicians and strange animals from the conquered territories, together with carts laden with treasure and captured armaments.

"The conqueror rode in a triumphal chariot," Patton goes on, "Dazed prisoners walking in chains before him. Sometimes his children -- robed in white -- stood with him in the chariot, or rode the trace horses. A slave stood behind the conqueror, holding a golden crown, and whispering in his ear a warning: That all glory is fleeting."

Trumpets sound. Fade out. Roll credits.

Watching President Obama at the White House almost one week ago now, I noticed the absence of anyone standing behind him, at least close enough to whisper anything in his ear.

[caption id="attachment_6061" align="aligncenter" width="300" caption="(AP)"][/caption]

So I'll do what I can for him from here.

Obama's win with 53 percent of the vote is the strongest finish by a Democrat running for president since Lyndon Johnson's 1964 landslide. The same is true for the number of people present -- 1.2 million who attended his inaugural celebration; a large number, but still not as many as those who came for LBJ (when the population of the country was half of what it is today). So he may believe he has a mandate. But he must remember than things in politics can change very quickly.

The Nov. 17, 1980 cover of Time magazine shows a smiling Ronald Reagan -- by now president-elect -- under the headline, "A Fresh Start." Reagan came into office with a mandate and the first Republican Senate in a generation. By 1982 the media was pronouncing him "a one term president" with a program that was dead in the water thanks to a post-recessionary economic hangover they blamed on "Reaganomics."

Two years later he was re-elected with the largest Electoral College landslide since the District of Columbia was given presidential electors, losing only D.C. and, by 7,000 votes, his opponent's home state of Minnesota.

George H.W. Bush turned in an impressive victory in 1988, winning the electoral and popular votes by strong margins. During the Gulf War his approval rating set records. And in November 1992 the American public turned him out in what USA Today, on Nov. 4, 1992 said was a "LANDSLIDE" in its headline.

"Clinton," the same day's Boston Globe reported, "rolls from sea to sea, ending GOP grip on presidency," based on his winning 43 percent of the popular vote in a three-way race. And by Aug. 16, 1993 Time magazine, showing a similar picture of Reagan from 1980 -- this time upside down -- explained how Clinton's budget singled "a new course for America" that was "Overturning the Reagan Era."

What was overturned, however, was the Clinton presidency -- and well before Monica Lewinsky. Within 18 months, thanks to midnight basketball and tax hikes, Clinton cost the Democrats their 40-year control of the House of Representatives, the U.S. Senate and hundreds of state legislative seats all across America. Within two years it was Clinton was explaining, in Reagan-lite terms, that "The era of big government is over" while trying to explain that the presidency remained "relevant" in the era of the Gingrich Congress. And then he plunged a knife into his political base by signing the third of the Republican's landmark welfare reform bills while claiming credit for it, after having vetoed the first two.

Most recently Republican plans for a Bush-Rove-designed permanent governing GOP national majority showed every sign of taking root before collapsing in the 2006 mid-term elections that returned control of Congress to the Democrats.

So President Obama, who is riding higher than high right now -- and whose aides seemed to suggest to The Washington Post that his presidency be measured by its actions, not in the first 100 days, but in the first 100 hours, would do well to remember these examples. There are more things than glory that are fleeting, including political capital and the public's approval.

Peter Roff, a former senior writer at United Press International, is a senior fellow at Frontiers of Freedom, an organization that advocates for educational freedom and reform.