Napoleon, love him or hate him, was still a shrewd politician and by far Washington's better in terms of military,
The question was not who was the better military leader. Napoleon obviously wins there. But as a political leader, Napoleon was a dictator who took the French Revolution and usurped it for his own aggrandizement. Since my standard for greatness in a politician is how much he advances the cause of liberty and democratic government for his people, Napoleon fails miserably as a political leader.
Augustus was one of the greatest political minds of history.
Augustus took a Republic and transformed it into a monarchy. Sorry, he fails the test, too.
Personally I'd rank Lincoln at the top, he faced a crisis with skill and effectiveness, if only Booth hadn't deemed it necessary to kill him, reconstruction could have been a lot smoother and less painful for the nation as a whole.
Ah, Dishonest Abe. Abe Lincoln "saved the Union," by denying the right of self-government to the people of eleven Southern States, who had democratically voted to withdraw from the Union, and forcing them to accept the rule of a government to which they no longer consented. He also set in motion processes which have lead to the increasing power of the federal government ever since, at the expense of the liberty of the American people. He too fails the test of greatness, IMHO.