 Most modern authorities have assessed McClellan as a poor battlefield general . A few historians view him as a highly capable commander whose reputation suffered unfairly at the hands of pro @-@ Lincoln partisans who made him a scapegoat for the Union 's military setbacks . After the war , Ulysses S. Grant was asked for his opinion of McClellan as a general . He replied , " McClellan is to me one of the mysteries of the war . " 
