RALF LOUIS GRAHAM NASH “I’m feeling optimistic that music can change the world with the right song in the right place,” says Graham Nash. “I give you an example of us (CSNY) doing ‘Ohio.’ And some of my songs, ‘Military Madness’ and ‘Chicago’ and ‘We Can Change the World.’ “I do believe we can change the world, but I’m not optimistic about the future of America. I see a country completely divided, basically, between smart people and stupid people. There’s a lot of both and there’s a battle going on now for the soul of democracy and I certainly hope that we can figure out how we can stop Trump …