The office of chief magistrate is supposed to command general respect. Respect, in a democratic setting, underlies voluntary obedience and compliance. A leader you don't respect receives -- at best -- grudging acknowledgement of his authority. It would seem in Obama's interest to give the best account he can -- consonant with the duty to campaign hard and effectively -- of his moral authority as chief magistrate. It would reinforce his capacity to govern.
But then point two, and this is more important. If presidents necessarily are human, with the usual run of human traits -- good, bad, indifferent -- the presidency as an institution transcends the lot. The presidency in a sense is all of us -- the sum of political experience and aspirations.
Modern people don't much like -- many actually hate and despise -- institutions, which have lives spanning generations, existing not by whim but by reason of prior and continuous arrangement. An institution is valued for the length of its whiskers.
The presidency of the United States is such an institution. It requires -- it demands outright -- a certain gravity, a certain dignity, as the occupant of the office goes about the fulfillment of his calling. A president without gravity or dignity, or if nothing else the outward appearance of both properties, debases and degrades. He wipes his shoes on the furniture, blows his nose on the tapestries. Institution? What institution?
What we have in such instance isn't a presidency, classically understood. We have instead a commercial office, a theater for ambition. Can we see what Romney is complaining about? A campaign of presidential vilification touches us all, debases us all. Don't feel it yet? Stick around.