Genrals to hold General of the Army or 5 star rank
Grant, Sherman, Sheridan, Marshall, MacArthur, Eisenhower, Arnold, Bradley.
Awarding Petreus a sixth star strikes me as the kind of jimcrack thingy that Obama would do. Too many things wrong with the idea to start to mention.
In 1976, President Ford posthumously appointed George Washington General of the Armies of the United States and specified that he would rank first among all officers of the Army, past and present. Presumably, therefore, Washington would need six stars.