(CNN) -- As rooms go, it's quite nice. It's shaped like an egg. It has a well-tended garden a few feet out the door, and then an expanse of lawn leading to a fence. It is certainly not the most ornate or luxurious room in the United States. Most five-star hotels have suites that out-glitter it. Any number of corporate CEOs boast offices that are larger and more lavishly outfitted. But the Oval Office at 1600 Pennsylvania Avenue in Washington has always been the object of a singular kind of yearning. Mitt Romney fervently wants to move into it in January; Barack Obama just as fervently wants not to move out. This fall's presidential campaign, which begins in earnest with the Republican National Convention this week, will determine whether it will be Romney or Obama who gets his wish.
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Bob Greene: Oval Office for some the most coveted room in the nation; however transient
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He says two fraught videos convey how ephemeral a president's time in the Oval Office is
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One shows outtakes of interview with supremely confident JFK just months before he died
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Other shows Nixon bantering awkwardly before resigning, ceding his yearned-for position
Here is a man who worked all his life to make it to this room, and now he -- as @placeholder, in a very different context, did before him -- is leaving it earlier than he thought he would have to.