coming up sunday morning, former nsc russet director gregory edmonds discussed russia's alleged role in the poisoning of a double agent in britain and meddling in the u.s. elections. then, the debut of our series, 1968: america in turmoil. marinissand david talk about the major political and diplomatic developments in the vietnam war. be sure to watch washington journal live at 7:00 eastern on sunday morning. join the discussion. c-span's q&a, colorado college professor talks about his book "imagining a great republic." >> i think the reading of major political classics is very empowering in terms of this country stands for something, very special, and the great they are- storytellers, saying our tribe wants to be something special. not just a city on a hill, but a city that cares and loves one another and wants to work with one another. and understands that politics is indispensable to bringing about progress for as much people as possible. >> sunday night at 8:00 eastern on c-span. next, the hearing of space a national security. general john raymond who heads the air force space co