Pope John Paul II gave one of his most inspired and impassioned speeches during a homily at Victory Square in Warsaw when he returned to Poland as Pope in 1979. (The homily may be found here; a documentary may be found here.)
In Memory and Identity John Paul II references this homily (p. 15) as a statement of the fundamental and most important limit to evil, namely the presence of Christ. To exclude Christ is make ourselves vulnerable to the power of evil. John Paul II saw Christ excluded on a daily basis by totalitarian ideologies and he feared the creeping exclusion of Chris in the west by liberal ideology. Let's look at few passages from the important homily.
In this homily he said: "To Poland the Church brought Christ, the key to understanding that great and fundamental reality that is man. For man cannot be fully understood without Christ. Or rather, man is incapable of understanding himself fully without Christ. He cannot understand who he is, nor what his true dignity is, nor what his vocation is, nor what his final end is. He cannot understand any of this without Christ.
Therefore Christ cannot be kept out of the history of man in any part of the globe, at any longitude or latitude of geography. The exclusion of Christ from the history of man is an act against man. Without Christ it is impossible to understand the history of Poland, especially the history of the people who have passed or are passing through this land. The history of people. The history of the nation is above all the history of people. And the history of each person unfolds in Jesus Christ. In him it becomes the history of salvation."
"The history of the nation deserves to be adequately appraised in the light of its contribution to the development of man and humanity, to intellect, heart and conscience. This is the deepest stream of culture. It is culture's firmest support, its core, its strength. It is impossible without Christ to understand and appraise the contribution of the Polish nation to the development of man and his humanity in the past and its contribution today."
This homily serves as a very nice context and focus for a reading of the book.