The American Experiment 111 Years Later

 TR has a famous quote about the "man in the arena" but the whole speech which includes it is interesting.  He's speaking as ex-President to the Sorbonne, and appeals to what France and US share: being a republic and democracy, an experiment in government.  The year is 1911 and the world is governed by monarchies. The excerpt:

Today I shall speak to you on the subject of individual citizenship, the one subject of vital importance to you, my hearers, and to me and my countrymen, because you and we are great citizens of great democratic republics. A democratic republic such as ours—an effort to realize in its full sense government by, of, and for the people—represents the most gigantic of all possible social experiments, the one fraught with great responsibilities alike for good and evil. The success of republics like yours and like ours means the glory, and our failure the despair, of mankind; and for you and for us the question of the quality of the individual citizen is supreme. Under other forms of government, under the rule of one man or very few men, the quality of the leaders is all-important. If, under such governments, the quality of the rulers is high enough, then the nations for generations lead a brilliant career, and add substantially to the sum of world achievement, no matter how low the quality of the average citizen; because the average citizen is an almost negligible quantity in working out the final results of that type of national greatness. But with you and us the case is different. With you here, and with us in my own home, in the long run, success or failure will be conditioned upon the way in which the average man, the average woman, does his or her duty, first in the ordinary, every-day affairs of life, and next in those great occasional cries which call for heroic virtues. The average citizen must be a good citizen if our republics are to succeed. The stream will not permanently rise higher than the main source; and the main source of national power and national greatness is found in the average citizenship of the nation. Therefore it behooves us to do our best to see that the standard of the average citizen is kept high; and the average cannot be kept high unless the standard of the leaders is very much higher. [emphasis added]

I guess WWI marked the change--the German, Russian, Italian, Austria-Hungary monarchies vanished and the US became more eminent in the world.