The New Deal generation of American historians wanted to see US history as a simple story of good and evil.I disagree. The New Deal historians did everything they could to cover up the evil of their heroes, and everything they could to uncover the evil of their enemies. Moral ambivalence was nothing of their methods. Moral obfuscation was the game. The white washing of Wilson's racism is a good start. Then we can add T. Roosevelt's extreme -- if not racism -- racial politics. Roosevelt upheld the black as a means, little more.
Above all, the New Deal historians were embittered by hatred for Harding. Harding, that blithering, blathering fool, that idiot, that corrupt ass... kicked Wilsonian democracy in the crotch. Harding killed Wilson. New Deal historians never forgave him this. Whenever they look back at the 1920s, the 1910s, the 1900s, even the 1890s (as seen in their treatment of McKinley, that nice, listless man), they framed it by Harding. To them, if a Republican led somehow to Harding, he was scum.
No, they weren't interested in good and evil. They were interested in good alone. Evil was for their enemies.
But about TR: his invitation of Booker T. Washington to the White House certainly was a high point in recognition of African Americans in his admittedly prejudiced era. TR also spoke out strongly against lynching. His treatment of Black soldiers in Texas was wrong and counterproductive, as were his racial views in general, but was he truly worse on race than were his predecessors?
You may remember a thread in the past few years criticizing current Presidential advisor Karl Rove's hero McKinley for abandoning the civil rights cause. I didn't buy that either, but I do think that the turn away from African American rights was continuous. I don't think there was less concern for civil rights under TR than under McKinley, because there was so little interest in Blacks in general. Nor was there more interest in African-Americans under Harrison's Presidency, though some Congressmen kept up the fight. You'd have to produce evidence to convince me that McKinley or Harrison was better for Blacks than Roosevelt.
Roosevelt's expressed racial views may lead to his being taken as more racist than preceding or following Presidents. He did believe in race, and he left a paper trail, though what race meant to him is open to question. It definitely did include color, but wasn't restricted to it. Roosevelt, though, came out of the ethnically more complex politics of New York and this did provide a place for African-Americans.
As to his using Negroes as a means, I'm not sure this differs from earlier or later practice. Roosevelt was certainly aware of the problems African-Americans faced in the political world. If his New York background helped TR to understand the politics of the melting pot, his Georgia ancestry meant that he had a long way to go to come to terms with Black aspirations. He certainly went further in that direction than Wilson. I'm not convinced that McKinley, a former Union officer, went further.