We have crossed the boundary that lies between Republic and Empire. If you ask when, the answer is that you cannot make a single stroke between day and night: the precise moment does not matter. There was no painted sign to say: "You are now entering Imperium." Yet it was a very old road and the voice of history was saying: "Whether you know it or not, the act of crossing may be irreversible." And now, not far ahead, is a sign that reads: "No U-turns."
It's a fine passage, but I think there's a certain irony (or at least an "irony") in the fact that he wrote it in 1952.
It reminds me of the thing that kept bugging me about Gore Vidal's American history novels. I love the series, especially Burr, but after a while I started to say to myself, "Just how many times can a country transform itself from a Republic into an Empire? Apparently it happens every 30 years or so."