Speaking of Russia Leaves the War, this passage from later in the same chapter as the other quote is an interesting reminder of how American entry into WWI came to be cast as a war of democracy against absolute rulers:

It is thus possible to say that while America’s entry into World War I was in no wise occasioned by the [February] Russian Revolution, this event did indeed affect the interpretation placed upon the war by the American government and public. In particular, it made possible to construct for the American war effort an ideological rationale which, had the Russian Revolution not occurred, would have been relatively unconvincing and difficult to maintain. This was, at the time, a most welcome possibility; and one can easily understand how strong was the temptation to take advantage of it. But it implied a commitment on the part of the United States government to precisely those assumptions concerning the Russian situation which, as we have just seen, were least likely to be fulfilled; namely, that Russian political life would advance at once toward a stable parliamentary system and that Russia would continue to wage war a a member of the Allied coalition. (p. 15-16)

As everyone knows, neither of these things occurred. By the time American soldiers were fighting in Europe, the post-tsarist government that had provided this “ideological rationale” for the war effort had already been overthrown, and Russia had made a separate peace. It is fitting that the first crusade for democracy involved such a complete misunderstanding of conditions in Russia, since virtually all subsequent democratist schemes seem to depend on ignorance about the countries that democratists want to turn into allies in their ideological struggle.