It is in the nature of a republic to have only a small territory ; otherwise it can hardly subsist. In a large republic, there are large fortunes, and consequently little moderation in the minds ; there are trusts too great to place into the hands of a citizen ; interests become individualized ; a man feels first that he can be happy, great, and glorious without his homeland, and soon that he can be great alone on the ruins of his homeland.
In a large republic, the common good is sacrificed to a thousand considerations, and subordinated to exceptions ; it depends on accidents. In a small one, the public good is better felt, better known, closer to each citizen ; abuses are less extensive, and consequently less protected.
What made Lacedæmon subsist so long was that after all the wars she still remained with her territory. The only goal of Lacedæmon was freedom ; the sole advantage of its freedom was glory.
It was the spirit of the Greek republics to content themselves with their lands as with their laws. Athens acquired ambition, and it spread to Lacedæmon ; but it was rather to command free peoples than to govern slaves, rather to lead the union than to break it up. All was lost when a monarchy arose, a government with a spirit tending more to expansion.
Without particular circumstances,  it is difficult for any government other than a republican one to subsist in a single city. A prince of such a small state would naturally seek to oppress, because he would have great authority and few means of enjoying it or commanding respect. He would therefore tread heavily on his people. On the other hand, such a prince would easily be oppressed by a foreign force, or even a domestic force ; the people could at any moment assemble and unite against him. Now, when a prince of a city is driven out of his city, the trial is over ; if he has several cities, the trial has merely begun.