U.S. President John F. Kennedy's speech in West Berlin, Germany, on June 26, 1963 remains relevant today for the same reasons that it resonated 50 years ago. Although it's true that marxism and communism has lost some of its inhumane and pernicious influence in the world, it still exists in some form, continuing to enslave the minds and bodies of its citizens.
You can replace the word "communism" noted in President Kennedy's speech with any other ideology, whether religious or secular, whose purpose and preoccupation is to restrict freedom, individual rights and democracy. Such western-inspired values, which date to the European Enlightenment, are too valuable to take for granted; they need be both practiced and protected.
One final point. It's important here to dispel one myth about the speech—one that has become an urban legend—namely, that President Kennedy's use of the now-famous phrase, Ich bin ein Berliner, was grammatically incorrect. This is a claim made by many media sources, including the New York Times, the Guardian, Time and BBC News. David Emery in an article in About.com writes:
Laying decades of misinformation to rest, linguist Jürgen Eichhoff undertook a concise grammatical analysis of Kennedy's statement for the academic journal Monatshefte in 1993. "'Ich bin ein Berliner' is not only correct," Eichhoff wrote, "but the one and only correct way of expressing in German what the President intended to say."
An actual Berliner would say, in proper German, "Ich bin Berliner." But that wouldn't have been the correct phrase for Kennedy to use. The indefinite article "ein" is required, Eichhoff explained, to express a metaphorical identification between subject and predicate. Otherwise, the speaker could be taken to say he is literally a citizen of Berlin, which was not Kennedy's intention.You can find the background to and the text of the complete speech here].