His courage is exhilarating. Even if you think his cause hopeless, Alexei Navalny, the Russian opposition leader and Putin-baiter, deserves our admiration. To return to Moscow after being poisoned, surely knowing arrest awaited him, is beyond brave. The chances are he will be crushed. But annihilation is not certain; and if one day he wins his battle with Putin, his return to Moscow this winter will become the stuff of legend.