MOSCOW—For the West, the downing one year ago of Malaysia Airlines Flight 17 underlined the brutality of Moscow’s hybrid intervention in eastern Ukraine. In Russia, the downing is still living large on television screens, blamed squarely on the Ukrainians—with the possible connivance of Western secret services.

Within hours of the crash on July 17, 2014, Russian state television began to spew a jumble of explanations for the tragedy, all of which fingered Kiev and absolved Russia and pro-Russian rebels in Ukraine of guilt....