I have been to the Tidal Basin around 5 or 6 times now and the Martin Luther King Jr.'s monument, to me, is by far the most powerful monument that I have ever seen. Maybe the Michelangelo in Florence tops it, but they are close. You can't miss the impression of power that the sculptor took from the 1964 "I Have A Dream" speech, where Dr. King said "Out of a mountain of despair, a stone of hope". A fitting tribute to a powerful American.