There are a lot of quotable passages in that book. Taylor Caldwell must had a really good crystal ball.
But my favorite Christmas scene is at the house where Arthur Carlson and the Minute Men await the final move. A plane flies overhead displaying the pattern of the forbidden old American flag, and the troops break out spontaneously into "The Star Spangled Banner". I used to get cold chills when I read this passage, but since the Christmas of 2008, I tend to break down and stop reading at this point.
The end is heartbreaking, but it's clear that the people need a narrative to explain what happened, and that narrative doesn't necessarily need to be factual.