In these tormented times (but did they really quiet in the end?), let's watch back the hope of the sixties. Not the May 1968 students' movement of Paris, more John Kennedy's and his contemporaries' sixties.
Found on a cover cancelled on 27 November 1967 in Bloomington, Indiana for an arrival in Belgium next December, via Brussels:
The brown stamp was the second one dedicated to the assassinated president. The pictorial "Pray for peace" cancellation is linked to his presidency, both inside and outside the United States.
One book more, harder to retrieve, but which contents lots of texts by these 1960s optimists, all three assassinated: John Kennedy and his brother Robert, and Martin Luther King. German telivision journalist Thilo Koch's Kämpfer für eine neue Welt [Fighters for a new world], 1968 published by C.J. Bucher.
Idealism, when you caught me...