Content vs delivery
From a delivery perspective, part of the US President's distinctive style is the use of the pause. Dramatic pauses after key phrases are scattered liberally throughout the speech. Dramatic pauses don't have to be long, just enough for your audience to focus on your words. If you listen carefully, you will also note hat here is a brief pause in the middle of words, dragging them out and adding to the sense that the President is weighing each word carefully before he delivers them. The measured pace creates a feeling of gravity which (if we refer to Tomasky's analysis) matches the downbeat mood of the message.