Here are some quotations on the matter:
Power is always dangerous. Power attracts the worst and corrupts the best.~ Edward Abbey
Because power corrupts, society’s demands for moral authority and character increase as the importance of the position increases.~ John Adams
It is said that power corrupts, but actually it’s more true that power attracts the corruptible. The sane are usually attracted by other things than power.~ David Brin
Power tends to corrupt, and absolute power corrupts absolutely. Great men are almost always bad men.~ Lord Acton 10 January 1834 – 19 June 1902),
It’s the Lord Acton quotation which is best known.
Lord Acton was a Roman Catholic Peer in the United Kingdom. He was a Liberal (in the sense of the old fashioned British Liberal Party) and a friend, advisor and confidante of British Premier William Ewart Gladstone (1809-1898)
(see http://www.bbc.co.uk/history/historic_figures/gladstone_william_ewart.shtml )
Acton’s famous quotation comes from his writing in response to the First Vatican Council’s declaration re Papal Infallibility (1870).
He was appalled by this. A fuller excerpt of what he said is well worth reading:
( The quotation comes from a letter which Acton sent to William Creighton, (Anglican) Bishop of London).
"I cannot accept your canon that we are to judge Pope and King unlike other men with a favourable presumption that they did no wrong. If there is any presumption, it is the other way, against the holders of power, increasing as the power increases. Historic responsibility has to make up for the want of legal responsibility. Power tends to corrupt, and absolute power corrupts absolutely. Great men are almost always bad men, even when they exercise influence and not authority: still more when you superadd the tendency or certainty of corruption by full authority. There is no worse heresy than the fact that the office sanctifies the holder of it”.
His last sentence is salient, and should be written on the heart of every President, Pope, Bishop, Member of Parliament, U.S. Representative, U.S. Senator, Church Minister et al.
There can be no special pleading by the holders of these high and/or influential offices.
They might all need to hear the wise words of Canon Ed Rodman of the Diocese of Massachusetts. To all leaders, or would be leaders Canon Rodman says “Do not believe your own propaganda”.