It was by HL Mencken and it was his obituary of his nemisis, William J Bryan:
It is the national custom to sentimentalize the dead, as it is to sentimentalize men about to be hanged. Perhaps I fall into that weakness here. The Bryan I shall remember is the Bryan of his last weeks on earth -- broken, furious, and infinitely pathetic. It was impossible to meet his hatred with hatred to match it. He was winning a battle that would make him forever infamous wherever enlightened men remembered it and him. Even his old enemy, Darrow, was gentle with him at the end. That cross-examination might have been ten times as devastating. It was plain to everyone that the old Berseker Bryan was gone -- that all that remained of him was a pair of glaring and horrible eyes.
But what of his life? Did he accomplish any useful thing? Was he, in his day, of any dignity as a man, and of any value to his fellow-men? I doubt it. Bryan, at his best, was simply a magnificent job-seeker. The issues that he bawled about usually meant nothing to him. He was ready to abandon them whenever he could make votes by doing so, and to take up new ones at a moment's notice. For years he evaded Prohibition as dangerous; then he embraced it as profitable. At the Democratic National Convention last year he was on both sides, and distrusted by both. In his last great battle there was only a baleful and ridiculous malignancy. If he was pathetic, he was also disgusting.
Bryan was a vulgar and common man, a cad undiluted. He was ignorant, bigoted, self-seeking, blatant and dishonest. His career brought him into contact with the first men of his time; he preferred the company of rustic ignoramuses. It was hard to believe, watching him at Dayton, that he had traveled, that he had been received in civilized societies, that he had been a high officer of state. He seemed only a poor clod like those around him, deluded by a childish theology, full of an almost pathological hatred of all learning, all human dignity, all beauty, all fine and noble things. He was a peasant come home to the dung-pile. Imagine a gentleman, and you have imagined everything that he was not.
The job before democracy is to get rid of such canaille. If it fails, they will devour it.
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http://www.etsu.edu/cas/history/docs/menckenbryan.htm